A302151 Number of 3Xn 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.
4, 1, 4, 5, 11, 34, 88, 271, 798, 2368, 7071, 21110, 63163, 188980, 565622, 1693239, 5069374, 15178832, 45451143, 136102762, 407567006, 1220499079, 3654940301, 10945255479, 32777313021, 98157159720, 293948595170, 880280943171
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..1..1..1..1. .0..1..0..1..1. .0..1..1..1..1. .0..1..1..0..1 ..1..1..0..1..1. .0..1..1..1..0. .1..1..1..1..1. .1..1..1..0..0 ..1..1..1..1..0. .1..1..0..1..0. .0..1..1..1..0. .1..1..0..0..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A302150.
Formula
Empirical: a(n) = 4*a(n-1) -4*a(n-2) +6*a(n-3) -10*a(n-4) +11*a(n-5) -24*a(n-6) +11*a(n-7) -45*a(n-8) +22*a(n-9) -38*a(n-10) +39*a(n-11) -21*a(n-12) +68*a(n-13) +28*a(n-14) +73*a(n-15) -25*a(n-16) -16*a(n-17) -37*a(n-18) -11*a(n-19) -11*a(n-20) -16*a(n-21) -7*a(n-22) +3*a(n-24) +a(n-25) for n>27
Comments