A302162 Number of nX7 0..1 arrays with every element equal to 0, 1 or 3 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
21, 185, 56, 206, 603, 1247, 2853, 6870, 15489, 35924, 84962, 195967, 453837, 1061993, 2464882, 5719363, 13329296, 30988342, 71989905, 167525699, 389592291, 905597726, 2106327411, 4898465680, 11389209332, 26486000403, 61593726193
Offset: 1
Keywords
Examples
Some solutions for n=5 ..0..0..1..1..0..1..0. .0..1..0..1..1..0..0. .0..1..1..0..0..1..0 ..0..1..0..1..0..1..1. .0..1..0..1..0..1..0. .0..1..0..1..0..1..0 ..0..1..0..1..0..1..0. .0..1..0..1..0..1..0. .0..1..0..1..0..1..0 ..0..1..0..1..0..1..0. .0..1..0..1..0..1..0. .0..1..0..1..0..1..1 ..0..1..0..0..1..1..0. .0..1..0..0..1..1..0. .1..0..0..1..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A302163.
Formula
Empirical: a(n) = a(n-1) +a(n-2) +11*a(n-3) -7*a(n-4) -7*a(n-5) -41*a(n-6) +26*a(n-7) +17*a(n-8) +74*a(n-9) -59*a(n-10) -19*a(n-11) -73*a(n-12) +82*a(n-13) +11*a(n-14) +44*a(n-15) -69*a(n-16) -5*a(n-17) -23*a(n-18) +34*a(n-19) +3*a(n-20) +14*a(n-21) -9*a(n-22) -a(n-23) -6*a(n-24) +a(n-25) +a(n-27) for n>39
Comments