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.

A318073 Number of nX6 0..1 arrays with every element unequal to 0, 1, 2 or 5 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

32, 89, 179, 372, 854, 3029, 9966, 31057, 102906, 339938, 1115341, 3686471, 12202268, 40357737, 133516203, 442017482, 1463416356, 4844264732, 16038582879, 53104714108, 175822278334, 582142483984, 1927505047124, 6381987620459
Offset: 1

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Author

R. H. Hardin, Aug 15 2018

Keywords

Comments

Column 6 of A318075.

Examples

			Some solutions for n=5
..0..0..0..0..0..0. .0..0..1..1..1..1. .0..1..1..1..1..0. .0..0..1..1..1..1
..0..0..0..0..0..0. .0..1..1..1..0..1. .1..0..0..1..0..1. .0..1..1..1..1..1
..0..0..0..0..0..1. .1..1..1..0..1..1. .1..1..1..1..1..1. .1..1..1..0..1..1
..0..0..0..0..1..1. .1..0..1..1..1..1. .1..1..1..1..1..1. .1..1..0..1..1..1
..0..0..0..1..1..1. .0..1..1..1..1..1. .0..0..0..0..0..0. .1..1..1..1..1..0
		

Crossrefs

Cf. A318075.

Formula

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +20*a(n-3) -53*a(n-4) +42*a(n-5) -141*a(n-6) +233*a(n-7) -201*a(n-8) +487*a(n-9) -268*a(n-10) +489*a(n-11) -1197*a(n-12) +587*a(n-13) -2030*a(n-14) +2132*a(n-15) -1266*a(n-16) +2926*a(n-17) -1010*a(n-18) +1350*a(n-19) -2698*a(n-20) +3123*a(n-21) -5723*a(n-22) +5669*a(n-23) -3510*a(n-24) -1261*a(n-25) +1023*a(n-26) +2441*a(n-27) -5509*a(n-28) +9188*a(n-29) -8116*a(n-30) +5375*a(n-31) -2481*a(n-32) +1789*a(n-33) -673*a(n-34) +1170*a(n-35) -4427*a(n-36) +4578*a(n-37) -4241*a(n-38) +2836*a(n-39) -553*a(n-40) -1029*a(n-41) +592*a(n-42) +939*a(n-43) -822*a(n-44) +491*a(n-45) -433*a(n-46) +91*a(n-47) +294*a(n-48) -222*a(n-49) -99*a(n-50) +125*a(n-51) -9*a(n-52) -25*a(n-53) +6*a(n-54) +3*a(n-55) -a(n-56) for n>61