A217633 Number of n X 4 arrays of the minimum value of corresponding elements and their horizontal and vertical neighbors in a random 0..1 n X 4 array.

6, 38, 244, 1418, 8706, 52120, 315378, 1900838, 11472148, 69210290, 417586442, 2519466108, 15201104542, 91714930026, 553357475040, 3338651662490, 20143579337906, 121535200857060, 733276159043790, 4424182455856594, 26693068489330768, 161051201588069830, 971693816818476190

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..64

Formula

Empirical: a(n) = 4*a(n-1) +20*a(n-2) -29*a(n-3) -124*a(n-4) +55*a(n-5) +330*a(n-6) -57*a(n-7) -498*a(n-8) -291*a(n-9) +965*a(n-10) +676*a(n-11) -991*a(n-12) -659*a(n-13) +771*a(n-14) +610*a(n-15) -581*a(n-16) -78*a(n-17) -36*a(n-18) +32*a(n-19) -94*a(n-20) +32*a(n-21) +68*a(n-22) -16*a(n-23).

Example

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

Crossrefs

Column 4 of A217637.

Sequence in context: A180030 A377114 A135030 * A162558 A215466 A147957

Adjacent sequences: A217630 A217631 A217632 * A217634 A217635 A217636

Keyword

nonn

Author

R. H. Hardin, Oct 09 2012

Status

approved