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A295413
Number of nX5 0..1 arrays with each 1 horizontally or vertically adjacent to 1, 2 or 3 1s.
1
12, 454, 10291, 240439, 5741797, 136204120, 3232240913, 76727059034, 1821136011730, 43225734223547, 1025994483127581, 24352654756464595, 578026399603342686, 13719842910804997191, 325649624449572326065
OFFSET
1,1
COMMENTS
Column 5 of A295416.
LINKS
FORMULA
Empirical: a(n) = 21*a(n-1) -19*a(n-2) +1762*a(n-3) +2976*a(n-4) +54764*a(n-5) +89653*a(n-6) +316576*a(n-7) +287742*a(n-8) -20679825*a(n-9) -44940268*a(n-10) +216658751*a(n-11) +618852508*a(n-12) -1025274808*a(n-13) -4191874824*a(n-14) +2114857458*a(n-15) +17367807580*a(n-16) +1683218669*a(n-17) -47511765414*a(n-18) -24987441190*a(n-19) +79504587457*a(n-20) +79176210027*a(n-21) -35208322572*a(n-22) -87836099993*a(n-23) -122776386003*a(n-24) -111692628042*a(n-25) +74324840678*a(n-26) +161097789530*a(n-27) +201019494411*a(n-28) +270708373108*a(n-29) +140937188144*a(n-30) +164331302880*a(n-31) +50684014656*a(n-32) +53238098432*a(n-33) +9806288896*a(n-34) +9366409216*a(n-35) +837222400*a(n-36) +734003200*a(n-37)
EXAMPLE
Some solutions for n=5
..0..0..0..0..0. .0..0..0..1..1. .0..0..0..0..1. .0..0..0..0..1
..0..0..0..0..0. .0..0..1..0..1. .0..0..0..0..1. .0..0..0..0..1
..1..1..1..1..0. .0..1..1..0..0. .0..1..1..1..1. .1..1..0..1..0
..0..0..1..0..0. .1..0..1..0..0. .0..0..0..0..1. .1..0..0..1..0
..0..0..0..1..1. .1..0..1..1..0. .0..1..1..1..1. .1..0..0..1..1
CROSSREFS
Cf. A295416.
Sequence in context: A192601 A092704 A322556 * A202799 A121348 A239365
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 22 2017
STATUS
approved