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.

A231421 Number of (2+1)X(n+1) 0..2 arrays with no element equal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..2 introduced in row major order.

Original entry on oeis.org

50, 1032, 20896, 424404, 8704406, 178277756, 3654045516, 74894704740, 1535161355750, 31467342399888, 645012980337444, 13221399981059518, 271010854744794084, 5555152819316036170, 113868962991822419034
Offset: 1

Views

Author

R. H. Hardin, Nov 08 2013

Keywords

Comments

Row 2 of A231419

Examples

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

Formula

Empirical: a(n) = 20*a(n-1) +56*a(n-2) -821*a(n-3) -2559*a(n-4) +2274*a(n-5) +11333*a(n-6) +75045*a(n-7) +58970*a(n-8) -744820*a(n-9) -338743*a(n-10) +3350990*a(n-11) -566226*a(n-12) -8533262*a(n-13) +6626396*a(n-14) +10836980*a(n-15) -13238580*a(n-16) -6337152*a(n-17) +13746128*a(n-18) -1255112*a(n-19) -8079152*a(n-20) +2081168*a(n-21) +460736*a(n-22) -1034208*a(n-23) +221216*a(n-24) -114304*a(n-25) -122880*a(n-26) -16384*a(n-27) -512*a(n-28)