A302082 Number of 3Xn 0..1 arrays with every element equal to 0, 1, 3 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.

4, 13, 33, 70, 154, 433, 1166, 3153, 8468, 22750, 61199, 165177, 445570, 1201785, 3241825, 8746118, 23596920, 63667249, 171782178, 463490985, 1250567970, 3374237398, 9104258583, 24564843989, 66280181642, 178835414969, 482529064189

Offset

1,1

Comments

Row 3 of A302081.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) -a(n-3) -2*a(n-4) -3*a(n-5) +5*a(n-6) -18*a(n-7) -a(n-8) +13*a(n-9) +18*a(n-10) -9*a(n-11) -13*a(n-12) +38*a(n-13) +13*a(n-14) -9*a(n-15) -18*a(n-16) +13*a(n-17) +a(n-18) -18*a(n-19) -5*a(n-20) -3*a(n-21) +2*a(n-22) -a(n-23) +3*a(n-25) +a(n-26) for n>27

Example

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

Crossrefs

Cf. A302081.

Sequence in context: A036420 A266094 A054039 * A124669 A036894 A227122

Adjacent sequences: A302079 A302080 A302081 * A302083 A302084 A302085

Keyword

nonn

Author

R. H. Hardin, Mar 31 2018

Status

approved