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.

A220029 Number of n X 5 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..1 n X 5 array.

Original entry on oeis.org

5, 12, 30, 61, 111, 187, 297, 450, 656, 926, 1272, 1707, 2245, 2901, 3691, 4632, 5742, 7040, 8546, 10281, 12267, 14527, 17085, 19966, 23196, 26802, 30812, 35255, 40161, 45561, 51487, 57972, 65050, 72756, 81126, 90197, 100007, 110595, 122001, 134266
Offset: 1

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Author

R. H. Hardin, Dec 03 2012

Keywords

Comments

Column 5 of A220032.

Examples

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

Crossrefs

Cf. A220032.

Formula

Empirical: a(n) = (1/24)*n^4 + (5/12)*n^3 + (11/24)*n^2 + (61/12)*n - 4 for n>1.
Conjectures from Colin Barker, Jul 30 2018: (Start)
G.f.: x*(5 - 13*x + 20*x^2 - 19*x^3 + 11*x^4 - 3*x^5) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>6.
(End)