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.

A252833 Number of n X 5 nonnegative integer arrays with upper left 0 and every value within 2 of its king move distance from the upper left and every value increasing by 0 or 1 with every step right, diagonally se or down.

Original entry on oeis.org

11, 53, 288, 1474, 6068, 18528, 42738, 79563, 129173, 191583, 266793, 354803, 455613, 569223, 695633, 834843, 986853, 1151663, 1329273, 1519683, 1722893, 1938903, 2167713, 2409323, 2663733, 2930943, 3210953, 3503763, 3809373, 4127783
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Examples

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

Crossrefs

Column 5 of A252836.

Formula

Empirical: a(n) = 6400*n^2 - 59190*n + 143483 for n>7.
Conjectures from Colin Barker, Dec 06 2018: (Start)
G.f.: x*(11 + 20*x + 162*x^2 + 758*x^3 + 2457*x^4 + 4458*x^5 + 3884*x^6 + 865*x^7+ 170*x^8 + 15*x^9) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>10.
(End)