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 1-7 of 7 results.

A269137 Number of n X 2 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

16, 148, 1164, 8532, 59916, 408596, 2727564, 17914580, 116170764, 745617300, 4745165964, 29984668756, 188330955276, 1176750424852, 7319499656844, 45347466532308, 279961285570572, 1722988944076436, 10574188575966348
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Examples

			Some solutions for n=4:
..2..0. .3..3. .1..0. .2..2. .3..0. .2..1. .0..0. .0..1. .3..3. .0..1
..2..2. .1..1. .1..1. .2..3. .1..0. .0..1. .0..1. .0..0. .1..1. .0..3
..3..1. .1..3. .3..1. .0..1. .0..1. .1..1. .1..1. .1..2. .1..1. .1..1
..1..1. .3..3. .0..0. .0..1. .0..0. .3..1. .0..2. .0..2. .3..0. .1..0
		

Crossrefs

Column 2 of A269143.

Formula

Empirical: a(n) = 12*a(n-1) - 38*a(n-2) + 12*a(n-3) - a(n-4) for n>5.
Empirical g.f.: 4*x*(4 - 11*x - x^2 - x^3 + x^4) / (1 - 6*x + x^2)^2. - Colin Barker, Jan 19 2019

A269138 Number of nX3 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

60, 1164, 18556, 275796, 3924212, 54199284, 732561916, 9740150372, 127846717716, 1660741102212, 21389485726684, 273519303765844, 3476418550368820, 43954347343683220, 553215363420258236, 6935081471870462788
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Comments

Column 3 of A269143.

Examples

			Some solutions for n=3
..3..2..2. .1..0..0. .0..0..2. .1..1..1. .3..1..0. .1..1..3. .1..3..1
..3..2..2. .2..0..2. .1..3..3. .0..3..1. .3..0..2. .3..3..3. .1..1..3
..3..3..2. .0..2..0. .3..1..1. .1..1..3. .2..0..0. .2..2..2. .1..0..1
		

Crossrefs

Cf. A269143.

Formula

Empirical: a(n) = 26*a(n-1) -199*a(n-2) +408*a(n-3) -463*a(n-4) +322*a(n-5) -141*a(n-6) +36*a(n-7) -4*a(n-8) for n>9

A269139 Number of nX4 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

216, 8532, 275796, 8317996, 240647068, 6766301156, 186315931804, 5049212790572, 135126561336764, 3579710280903028, 94040960852579428, 2453204481574556084, 63613980689923027716, 1641094486943583990844, 42147014968744168530996
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Comments

Column 4 of A269143.

Examples

			Some solutions for n=2
..2..3..2..2. .2..3..1..3. .0..0..1..1. .1..1..3..1. .1..1..0..1
..2..2..2..3. .3..1..1..2. .0..1..1..0. .0..1..3..3. .0..1..1..3
		

Crossrefs

Cf. A269143.

Formula

Empirical: a(n) = 58*a(n-1) -1093*a(n-2) +7680*a(n-3) -27078*a(n-4) +58958*a(n-5) -88914*a(n-6) +82212*a(n-7) -35159*a(n-8) -20796*a(n-9) +39556*a(n-10) -11364*a(n-11) -13593*a(n-12) +9618*a(n-13) +429*a(n-14) -2060*a(n-15) +434*a(n-16) +166*a(n-17) -92*a(n-18) +16*a(n-19) -a(n-20) for n>22

A269140 Number of nX5 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

756, 59916, 3924212, 240647068, 14197016484, 815458664276, 45920055321732, 2546667557472940, 139535357045338964, 7570570235882777884, 407418697407850105348, 21776207050517593512788, 1157149832292866826527492
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Comments

Column 5 of A269143.

Examples

			Some solutions for n=2
..0..1..3..3..3. .2..3..2..3..2. .3..1..1..3..2. .2..3..1..0..0
..1..3..2..2..3. .0..2..3..3..2. .1..0..2..3..2. .1..3..1..0..0
		

Crossrefs

Cf. A269143.

Formula

Empirical: a(n) = 134*a(n-1) -6403*a(n-2) +137212*a(n-3) -1537987*a(n-4) +10006762*a(n-5) -41364815*a(n-6) +107588656*a(n-7) -111196320*a(n-8) -399050332*a(n-9) +2108507944*a(n-10) -4098003684*a(n-11) +445179883*a(n-12) +18009896226*a(n-13) -42207232033*a(n-14) +12581717548*a(n-15) +122544940860*a(n-16) -203283873760*a(n-17) -79843687188*a(n-18) +508551706160*a(n-19) -240288894385*a(n-20) -648319426210*a(n-21) +662670918703*a(n-22) +480938145704*a(n-23) -858808887300*a(n-24) -176689259732*a(n-25) +734283407564*a(n-26) -39751157620*a(n-27) -450104705459*a(n-28) +101139044518*a(n-29) +200718146529*a(n-30) -72282159428*a(n-31) -63674380919*a(n-32) +31546829386*a(n-33) +13183985923*a(n-34) -9057688788*a(n-35) -1275648164*a(n-36) +1571020336*a(n-37) -67398016*a(n-38) -125671104*a(n-39) +17151168*a(n-40) +3564288*a(n-41) -665856*a(n-42) for n>45

A269141 Number of nX6 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

2592, 408596, 54199284, 6766301156, 815458664276, 95884587957284, 11067174233536260, 1259009098075800036, 141573069581490127524, 15769412440038867100180, 1742724618979587037657388
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Comments

Column 6 of A269143.

Examples

			Some solutions for n=2
..2..0..2..3..2..2. .0..2..3..1..0..0. .0..2..0..1..3..3. .1..1..1..1..1..1
..0..1..3..3..2..3. .0..2..1..1..0..0. .0..2..1..3..3..1. .0..1..3..3..1..3
		

Crossrefs

Cf. A269143.

A269142 Number of nX7 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

8748, 2727564, 732561916, 186315931804, 45920055321732, 11067174233536260, 2621894498331024092, 612729907775635265268, 141617828339474744759764, 32434464000726413874379876, 7371987566769862222037312812
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Comments

Column 7 of A269143.

Examples

			Some solutions for n=1
..1..3..3..1..1..3..2. .2..3..3..2..2..2..1. .2..2..3..1..0..0..2
		

Crossrefs

Cf. A269143.

A269136 Number of n X n 0..3 arrays with some element plus some horizontally, antidiagonally or vertically adjacent neighbor totalling three no more than once.

Original entry on oeis.org

4, 148, 18556, 8317996, 14197016484, 95884587957284, 2621894498331024092, 294433751149574057834796, 137064853562490916405823252564, 266206369700280385363973380215109284
Offset: 1

Views

Author

R. H. Hardin, Feb 20 2016

Keywords

Comments

Diagonal of A269143.

Examples

			Some solutions for n=3
..2..2..3. .0..0..2. .2..1..1. .2..3..2. .0..0..1. .3..1..3. .0..1..3
..3..2..3. .0..2..2. .0..0..1. .3..2..2. .1..1..3. .3..1..3. .3..1..3
..3..2..2. .0..0..1. .1..1..1. .3..2..2. .0..2..2. .3..2..3. .1..3..1
		

Crossrefs

Cf. A269143.
Showing 1-7 of 7 results.