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.

A202809 Number of nX5 nonnegative integer arrays with each row and column increasing from zero by 0, 1 or 2.

Original entry on oeis.org

1, 15, 356, 8232, 146300, 1874539, 17870566, 133496644, 817995997, 4261304129, 19398449839, 78815353079, 290571063342, 984899160732, 3101890356933, 9156259810369, 25514373644936, 67521447453170, 170570662562363
Offset: 1

Views

Author

R. H. Hardin Dec 24 2011

Keywords

Comments

Column 5 of A202812

Examples

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

Formula

Empirical: a(n) = (107411/608225502044160000)*n^20 + (107411/8688935743488000)*n^19 + (292049/711374856192000)*n^18 + (4388269/533531142144000)*n^17 + (17087621/156920924160000)*n^16 + (30492463/31384184832000)*n^15 + (153451759/26900729856000)*n^14 + (33671947/1681295616000)*n^13 + (151751213/4389396480000)*n^12 + (341775353/4828336128000)*n^11 + (8743193411/9656672256000)*n^10 + (10646538107/2414168064000)*n^9 + (5850968901581/941525544960000)*n^8 - (13679248369/3362591232000)*n^7 + (193043821457/3923023104000)*n^6 + (103097176421/653837184000)*n^5 - (5199936999869/37050773760000)*n^4 + (12260594911/61751289600)*n^3 + (692087587/1185125760)*n^2 + (33368033/232792560)*n