On the Eccentric Connectivity Polynomial of <span class="nowrap"><svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.06579971pt" id="M1" height="11.8441pt" version="1.1" viewBox="-0.0657574 -11.7783 15.9607 11.8441" width="15.9607pt"><g transform="matrix(.017,0,0,-0.017,0,0)"><path id="g198-7" d="M896 662C863 643 826 624 783 624C682 624 539 680 429 680C328 680 253 659 202 616C163 583 138 537 138 484C138 399 208 349 283 349C396 349 466 417 492 554L472 555C436 442 385 379 286 379C234 379 179 410 179 491C179 578 257 634 382 634C475 634 622 574 731 574C796 574 862 610 907 647L896 662ZM657 568C577 499 520 440 477 341L463 310C368 277 286 233 247 186L260 171C320 211 380 237 437 256C349 77 281 31 184 31C124 31 83 59 78 94H80C87 83 101 81 109 81C137 81 153 104 153 131S130 180 103 180C68 180 43 154 43 111C43 34 123 0 192 0C335 0 469 75 546 282C599 291 640 293 661 294C653 267 650 244 650 224V206L709 226C706 235 706 245 706 252C706 271 706 289 714 312C758 333 786 368 786 387C786 403 775 409 763 409C744 409 712 391 685 352C644 351 604 345 564 337C595 433 622 506 671 554L657 568Z"/></g></svg>-</span>Sum of Connected Graphs

<div>The linear phenylene <span class="nowrap"><svg height="12.5794pt" id="M138" style="vertical-align:-3.29107pt" version="1.1" viewbox="-0.0498162 -9.28833 93.0039 12.5794" width="93.0039pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M584 650H137L131 622C214 614 217 612 200 521L125 127C109 41 101 35 23 28L17 0H288L294 28C201 35 193 42 209 128L242 309H348C440 309 442 300 443 226H471L510 422H482C452 354 449 348 357 348H251L295 575C302 609 304 615 338 615H426C502 615 517 604 526 581C534 560 536 524 537 492L565 494C574 554 583 631 584 650Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,6.786,3.132)"><path d="M504 89L488 119C453 85 428 69 416 69C408 69 405 75 412 102L462 304C492 438 460 451 436 451S388 441 356 423C311 397 229 336 170 256H168L189 340C208 418 200 451 177 451C144 451 82 413 24 352L40 322C65 345 98 369 108 369C114 369 119 363 112 335L28 -3L36 -12C54 -3 83 4 112 10C125 73 138 122 153 174C205 258 328 382 376 382C395 382 399 369 384 305L330 93C312 25 323 -12 351 -12C378 -12 439 21 504 89Z"></path></g><g transform="matrix(.013,0,0,-0.013,15.593,0)"><path d="M535 323V373H52V323H535ZM535 138V188H52V138H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,26.856,0)"><path d="M856 669C824 657 796 643 772 628C709 667 631 687 551 687C314 687 158 548 158 412C158 332 216 282 300 282C445 282 516 426 527 561H507C478 406 414 312 302 312C245 312 199 352 199 408C199 535 345 657 550 657C617 657 687 644 742 609C644 538 583 430 495 271C383 71 317 16 193 16C122 16 73 60 73 95H75C82 84 97 83 105 83C133 83 148 106 148 131C148 160 125 179 97 179C64 179 38 151 38 108C38 42 104 -15 211 -15C368 -15 496 71 610 302C672 426 704 522 770 588C803 559 825 518 825 465C825 382 787 316 731 316C710 316 697 328 697 345C697 358 700 380 733 399L723 417C688 398 665 367 665 338C665 303 688 272 737 272C821 272 886 359 886 447C886 516 850 572 797 612C816 627 836 639 863 650L856 669Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,38.686,3.132)"><path d="M290 377C321 398 342 415 358 430C378 450 389 473 389 502C389 578 329 635 238 635H237C184 635 137 610 109 578L64 515L88 493C112 529 154 573 208 573S303 542 303 482C303 409 233 370 141 341L149 308C165 313 190 319 215 319C272 319 341 283 341 193C342 98 292 43 222 43C163 43 122 72 96 94C88 101 79 100 70 94C61 87 47 73 46 60C44 47 48 37 62 23C76 10 118 -12 165 -12C238 -12 430 62 430 223C430 297 379 359 290 375V377Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,43.117,3.132)"><path d="M504 89L488 119C453 85 428 69 416 69C408 69 405 75 412 102L462 304C492 438 460 451 436 451S388 441 356 423C311 397 229 336 170 256H168L189 340C208 418 200 451 177 451C144 451 82 413 24 352L40 322C65 345 98 369 108 369C114 369 119 363 112 335L28 -3L36 -12C54 -3 83 4 112 10C125 73 138 122 153 174C205 258 328 382 376 382C395 382 399 369 384 305L330 93C312 25 323 -12 351 -12C378 -12 439 21 504 89Z"></path></g><g transform="matrix(.013,0,0,-0.013,48.309,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,52.807,0)"><path d="M805 658H719L589 415C537 319 349 15 237 15C214 15 208 28 208 43C208 59 219 86 247 130L433 417C464 464 471 506 471 541C471 638 384 687 292 687C164 687 36 597 36 474C36 406 83 360 151 360C238 360 296 442 309 509H289C265 440 225 390 150 390C103 390 77 426 77 474C77 582 175 652 283 652C340 652 404 619 404 568C404 541 397 512 368 467L223 240C170 155 153 111 153 73C153 18 186 -15 234 -15C290 -15 367 41 439 138L442 137C427 106 425 83 425 66C425 18 463 -12 511 -12C575 -12 638 42 714 134L693 147C621 63 565 18 525 18C506 18 492 28 492 53C492 60 493 77 509 108L805 658Z"></path></g><g transform="matrix(.013,0,0,-0.013,63.753,0)"><path d="M275 270C275 450 212 609 64 710L45 686C145 604 203 442 203 270S147 -63 45 -147L64 -170C213 -68 275 89 275 270Z"></path></g><g transform="matrix(.013,0,0,-0.013,68.251,0)"><path d="M535 0V548H53V0H111V498H477V0H535Z"></path></g><g transform="matrix(.013,0,0,-0.013,75.91,0)"><path d="M856 669C824 657 796 643 772 628C709 667 631 687 551 687C314 687 158 548 158 412C158 332 216 282 300 282C445 282 516 426 527 561H507C478 406 414 312 302 312C245 312 199 352 199 408C199 535 345 657 550 657C617 657 687 644 742 609C644 538 583 430 495 271C383 71 317 16 193 16C122 16 73 60 73 95H75C82 84 97 83 105 83C133 83 148 106 148 131C148 160 125 179 97 179C64 179 38 151 38 108C38 42 104 -15 211 -15C368 -15 496 71 610 302C672 426 704 522 770 588C803 559 825 518 825 465C825 382 787 316 731 316C710 316 697 328 697 345C697 358 700 380 733 399L723 417C688 398 665 367 665 338C665 303 688 272 737 272C821 272 886 359 886 447C886 516 850 572 797 612C816 627 836 639 863 650L856 669Z"></path></g><g transform="matrix(.0091,0,0,-0.0091,87.74,3.132)"><path d="M414 144C384 79 371 75 317 75H135L276 221C367 316 408 376 408 465C408 570 327 635 237 635C179 635 131 609 100 575L42 494L67 471C94 510 138 565 205 565C277 565 321 517 321 435C321 348 258 270 195 195C146 137 88 81 33 26V0H411C423 44 433 88 446 135L414 144Z"></path></g></svg>.</span></div>

Complexity

fig2

Figure 2

Figure 2: On the Eccentric Connectivity Polynomial of <span class="nowrap"><svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.06579971pt" id="M1" height="11.8441pt" version="1.1" viewBox="-0.0657574 -11.7783 15.9607 11.8441" width="15.9607pt"><g transform="matrix(.017,0,0,-0.017,0,0)"><path id="g198-7" d="M896 662C863 643 826 624 783 624C682 624 539 680 429 680C328 680 253 659 202 616C163 583 138 537 138 484C138 399 208 349 283 349C396 349 466 417 492 554L472 555C436 442 385 379 286 379C234 379 179 410 179 491C179 578 257 634 382 634C475 634 622 574 731 574C796 574 862 610 907 647L896 662ZM657 568C577 499 520 440 477 341L463 310C368 277 286 233 247 186L260 171C320 211 380 237 437 256C349 77 281 31 184 31C124 31 83 59 78 94H80C87 83 101 81 109 81C137 81 153 104 153 131S130 180 103 180C68 180 43 154 43 111C43 34 123 0 192 0C335 0 469 75 546 282C599 291 640 293 661 294C653 267 650 244 650 224V206L709 226C706 235 706 245 706 252C706 271 706 289 714 312C758 333 786 368 786 387C786 403 775 409 763 409C744 409 712 391 685 352C644 351 604 345 564 337C595 433 622 506 671 554L657 568Z"/></g></svg>-</span>Sum of Connected Graphs 

Complexity

On the Eccentric Connectivity Polynomial of -Sum of Connected Graphs

Figure 2