cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-8 of 8 results.

A201237 Number of ways to place 3 non-attacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 6, 208, 1300, 4908, 14112, 34112, 73008, 142700, 259908, 447312, 734812, 1160908, 1774200, 2635008, 3817112, 5409612, 7518908, 10270800, 13812708, 18316012, 23978512, 31027008, 39720000, 50350508, 63249012, 78786512, 97377708, 119484300, 145618408
Offset: 1

Views

Author

Vaclav Kotesovec, Nov 28 2011

Keywords

Comments

A wazir is a leaper [0,1].

Crossrefs

Formula

a(n) = n^2*(n^4-15*n^2+62)/6, n>=4.
G.f.: -2*x^3 * (3*x^7 - 15*x^6 + 25*x^5 - 7*x^4 - 17*x^3 - 15*x^2 + 83*x + 3)/(x-1)^7.

A201238 Number of ways to place 4 non-attacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 228, 3850, 27225, 122892, 423152, 1213380, 3046025, 6907890, 14454972, 28330822, 52586065, 93218400, 158854080, 261593552, 418045617, 650576150, 988799100, 1471339170, 2147897257, 3081651412, 4352027760, 6057877500, 8321097785, 11290735962
Offset: 1

Views

Author

Vaclav Kotesovec, Nov 28 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[x^3*(8 x^9 - 54 x^8 + 189 x^7 - 551 x^6 + 1404 x^5 - 2552 x^4 + 2685 x^3 - 783 x^2 - 1798 x - 228)/(x - 1)^9, {x, 0, 20}], x] (* Wesley Ivan Hurt, Jan 19 2017 *)

Formula

a(n) = n^2*(n^2-11)*(n^4 - 19n^2 + 114)/24, n>=5.
G.f.: x^4 * (8x^9 - 54x^8 + 189x^7 - 551x^6 + 1404x^5 - 2552x^4 + 2685x^3 - 783x^2 - 1798x - 228)/(x-1)^9.

A201239 Number of ways to place 5 non-attacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 128, 6745, 100332, 754453, 3830016, 15038541, 49207020, 140410699, 360001152, 846775007, 1855033964, 3828109545, 7507096576, 14087087961, 25436160108, 44395753647, 75184958080, 123935571963, 199389702380, 313797119069, 484055619840, 733144325125
Offset: 1

Views

Author

Vaclav Kotesovec, Nov 28 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Formula

a(n) = n^2*(n^8 - 50n^6 + 995n^4 - 9370n^2 + 35424)/120, n>=6.
G.f.: -x^4 * (10x^12 - 110x^11 + 685x^10 - 2771x^9 + 6946x^8 - 9350x^7 + 1710x^6 + 15214x^5 - 21392x^4 + 656x^3 + 33177x^2 + 5337x + 128)/(x-1)^11.

A201240 Number of ways to place 6 non-attacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 56, 7100, 252792, 3378942, 26249184, 144455454, 625745100, 2271361422, 7192874328, 20427662398, 53065637212, 127956238350, 289628321664, 620834113614, 1269178026012, 2488676915070, 4702895069400, 8598589878606, 15261688799500, 26371002575326
Offset: 1

Views

Author

Vaclav Kotesovec, Nov 28 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Formula

a(n) = n^2*(n^10 - 75*n^8 + 2365*n^6 - 39285*n^4 + 345034*n^2 - 1288680)/720, n>=7.
G.f.: 2*x^4 * (6*x^15 - 103*x^14 + 873*x^13 - 4241*x^12 + 12757*x^11 - 26112*x^10 + 45344*x^9 - 90774*x^8 + 189180*x^7 - 293907*x^6 + 260273*x^5 - 25077*x^4 - 315215*x^3 - 82430*x^2 - 3186*x - 28)/(x-1)^13.

A201241 Number of ways to place 7 non-attacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 16, 4450, 442980, 11281312, 139580160, 1103589198, 6433276500, 30047250222, 118507673088, 408912072478, 1265701033492, 3579712962750, 9380986518528, 23027843919870, 53409035159316, 117860600410206, 248890790976000, 505371757001454, 990655558290772
Offset: 1

Views

Author

Vaclav Kotesovec, Nov 28 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Formula

a(n) = n^2*(n^12 - 105*n^10 + 4795*n^8 - 122115*n^6 + 1834084*n^4 - 15461460*n^2 + 57441600)/5040, n>=8.
G.f.: -2*x^4 * (7*x^18 - 177*x^17 + 1965*x^16 - 12491*x^15 + 53736*x^14 - 175854*x^13 + 461641*x^12 - 942615*x^11 + 1320318*x^10 - 788656*x^9 - 1206129*x^8 + 3443471*x^7 - 3128600*x^6 - 552570*x^5 + 7435235*x^4 + 2548291*x^3 + 188955*x^2 + 2105*x + 8)/((x-1)^15).

A201242 Number of ways to place 8 non-attacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 2, 1550, 546516, 28482279, 585632520, 6829066665, 54504255500, 331490619174, 1642426038486, 6930083422496, 25686190415144, 85541928717375, 260349711114720, 733731834393719, 1934755847570808, 4813391235753128, 11375736647373750, 25684539545337246
Offset: 1

Views

Author

Vaclav Kotesovec, Nov 28 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Formula

a(n) = n^2*(n^14 - 140n^12 + 8722n^10 - 313880n^8 + 7061089n^6 - 99573740n^4 + 817978188n^2 - 3033601200)/40320, n>=9.
G.f.: x^4 * (16x^21 - 566x^20 + 8182x^19 - 67700x^18 + 377824x^17 - 1531112x^16 + 4601788x^15 - 10205035x^14 + 16637339x^13 - 21628151x^12 + 32135719x^11 - 68863352x^10 + 138461546x^9 - 189569712x^8 + 133644570x^7 + 20663373x^6 - 378949513x^5 - 174710713x^4 - 19400947x^3 - 520438x^2 - 1516x - 2)/(x-1)^17.

A201547 Number of ways to place 9 nonattacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 0, 250, 480916, 54916456, 1962132800, 34690541994, 385983794500, 3095143575007, 19437996015280, 100963195651565, 450398154002132, 1773257833600750, 6288010190509312, 20398342362118678, 61282868654684052, 172190699515632837, 456120623076014000
Offset: 1

Views

Author

Vaclav Kotesovec, Dec 02 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Formula

Explicit formula: n^18/362880 - n^16/2016 + 349*n^14/8640 - 467*n^12/240 + 1049629*n^10/17280 - 121049*n^8/96 + 1546301783*n^6/90720 - 346878319*n^4/2520 + 4595485*n^2/9, n>=10.
G.f.: -x^5*(18*x^23 - 854*x^22 + 15942*x^21 - 168082*x^20 + 1174353*x^19 - 5878707*x^18 + 22139332*x^17 - 65539648*x^16 + 159915785*x^15 - 334575275*x^14 + 598795512*x^13 - 842713520*x^12 + 703597341*x^11 + 289921121*x^10 - 2021527454*x^9 + 3166171570*x^8 - 1944444195*x^7 - 501647511*x^6 + 11035282966*x^5 + 6335694166*x^4 + 1000714522*x^3 + 45821802*x^2 + 476166*x + 250)/(x-1)^19.

A201548 Number of ways to place 10 nonattacking wazirs on an n X n toroidal board.

Original entry on oeis.org

0, 0, 0, 0, 10, 308574, 81442802, 5296005568, 146127335256, 2309813476870, 24738873315596, 198759048859008, 1279605298916568, 6906427308782106, 32277449304595350, 133788325435448576, 500896430870051174, 1718268150463137018, 5462521782760829320, 16243031089247644800
Offset: 1

Views

Author

Vaclav Kotesovec, Dec 02 2011

Keywords

Comments

Wazir is a leaper [0,1].

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[2 x^4 (10 x^26 - 615 x^25 + 14637 x^24 - 193410 x^23 + 1669110 x^22 - 10270682 x^21 + 47718030 x^20 - 174153546 x^19 + 511148331 x^18 - 1213451007 x^17 + 2302816572 x^16 - 3418379599 x^15 + 4006461091 x^14 - 4626995415 x^13 + 8410419611 x^12 - 19068629603 x^11 + 33871890471 x^10 - 39181017568 x^9 + 18018811352 x^8 - 5120263515 x^7 - 178499919965 x^6 - 123414145507 x^5 - 25801931589 x^4 - 1825246983 x^3 - 37482424 x^2-154182 x - 5) / (x - 1)^21, {x, 0, 50}], x] (* Vincenzo Librandi, Jun 04 2013 *)

Formula

Explicit formula: n^20/3628800 - n^18/16128 + 773*n^16/120960 - 761*n^14/1920 + 2820613*n^12/172800 - 356093*n^10/768 + 412940467*n^8/45360 - 2408161207*n^6/20160 + 24029851729*n^4/25200 - 3541971*n^2, n>=11.
G.f.: 2*x^5*(10*x^26 - 615*x^25 + 14637*x^24 - 193410*x^23 + 1669110*x^22 - 10270682*x^21 + 47718030*x^20 - 174153546*x^19 + 511148331*x^18 - 1213451007*x^17 + 2302816572*x^16 - 3418379599*x^15 + 4006461091*x^14 - 4626995415*x^13 + 8410419611*x^12 - 19068629603*x^11 + 33871890471*x^10 - 39181017568*x^9 + 18018811352*x^8 - 5120263515*x^7 - 178499919965*x^6 - 123414145507*x^5 - 25801931589*x^4 - 1825246983*x^3 - 37482424*x^2 - 154182*x - 5)/(x-1)^21.
Showing 1-8 of 8 results.