A269087 Number of nX6 binary arrays with some element plus some horizontally, vertically or antidiagonally adjacent neighbor totalling two not more than once.
41, 467, 5387, 55620, 555789, 5372270, 50865307, 473602013, 4353444165, 39602482120, 357186481377, 3198535920085, 28468239800885, 252053488597419, 2221493915335639, 19501164969933904, 170584538930223039
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..0..0..0..1..0. .0..0..1..0..0..1. .1..0..0..0..1..0. .0..1..0..0..0..0 ..1..0..0..0..0..0. .0..0..0..1..0..0. .0..0..0..0..0..1. .0..0..0..0..0..0 ..0..0..1..0..0..0. .1..0..0..0..0..0. .1..0..1..0..0..0. .0..1..0..0..0..1 ..0..0..0..1..0..1. .0..0..1..0..0..0. .0..0..1..0..0..0. .0..0..1..0..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A269089.
Formula
Empirical: a(n) = 2*a(n-1) +83*a(n-2) +210*a(n-3) -1918*a(n-4) -13444*a(n-5) -27431*a(n-6) +22868*a(n-7) +172414*a(n-8) +91292*a(n-9) -572846*a(n-10) -576908*a(n-11) +1569339*a(n-12) +1662464*a(n-13) -4129647*a(n-14) -2739590*a(n-15) +10005684*a(n-16) +128072*a(n-17) -18820309*a(n-18) +14239344*a(n-19) +18275195*a(n-20) -39512592*a(n-21) +16595129*a(n-22) +32600294*a(n-23) -63035320*a(n-24) +55225574*a(n-25) -27556538*a(n-26) +5959238*a(n-27) +1367780*a(n-28) -935764*a(n-29) -205936*a(n-30) +253428*a(n-31) -6946*a(n-32) -44268*a(n-33) +5192*a(n-34) +6896*a(n-35) -1085*a(n-36) -848*a(n-37) +74*a(n-38) +94*a(n-39) +3*a(n-40) -6*a(n-41) -a(n-42)
Comments