A231972 Number of (n+1)X(3+1) 0..1 arrays with no element having a strict majority of its horizontal and vertical neighbors equal to one

36, 169, 841, 4489, 24964, 136900, 741321, 4024036, 21911761, 119268241, 648771841, 3529072836, 19199427844, 104453715249, 568259668900, 3091481744121, 16818570092025, 91498158928089, 497777418977476

Offset

1,1

Comments

Column 3 of A231977

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-1) +8*a(n-2) +36*a(n-3) +90*a(n-4) +170*a(n-5) +66*a(n-6) -303*a(n-7) -268*a(n-8) +124*a(n-9) +40*a(n-10) -200*a(n-11) -184*a(n-12) -96*a(n-13) +57*a(n-14) +146*a(n-15) +36*a(n-16) -4*a(n-17) +22*a(n-18) -10*a(n-19) +6*a(n-20) -a(n-21)

Example

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

Crossrefs

Sequence in context: A338390 A268905 A017054 * A330770 A166708 A211731

Adjacent sequences: A231969 A231970 A231971 * A231973 A231974 A231975

Keyword

nonn

Author

R. H. Hardin, Nov 16 2013

Status

approved