A269040 Number of 6 X n 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once.
0, 7128, 67104, 1114848, 14710368, 208867428, 2783857776, 37310632920, 488972134752, 6374741325108, 82212554730696, 1054083281172600, 13425573904100400, 170167484580493980, 2146806101503300608
Offset: 1
Keywords
Examples
Some solutions for n=3 ..0..1..2. .1..0..1. .1..0..1. .0..0..1. .1..0..0. .1..0..0. .0..2..2 ..2..1..2. .1..2..1. .0..0..0. .0..0..0. .1..0..1. .1..0..0. .2..1..2 ..0..1..2. .1..2..1. .1..1..0. .0..0..1. .0..0..0. .1..2..1. .0..1..0 ..2..1..0. .1..0..1. .0..0..0. .0..0..0. .1..0..1. .1..2..1. .0..0..0 ..2..1..2. .1..2..0. .1..0..0. .0..0..0. .1..0..0. .2..2..1. .0..0..0 ..1..2..2. .1..0..1. .1..0..1. .0..1..2. .0..1..0. .2..2..1. .1..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A269035.
Formula
Empirical: a(n) = 12*a(n-1) +182*a(n-2) -1820*a(n-3) -15113*a(n-4) +101664*a(n-5) +646022*a(n-6) -3003324*a(n-7) -15725808*a(n-8) +55305760*a(n-9) +234926070*a(n-10) -698528578*a(n-11) -2270736611*a(n-12) +6320752450*a(n-13) +14600825558*a(n-14) -41434331996*a(n-15) -62768577651*a(n-16) +196263429930*a(n-17) +176943063476*a(n-18) -669462409316*a(n-19) -305019512324*a(n-20) +1647405492614*a(n-21) +230358934675*a(n-22) -2942270801898*a(n-23) +243588718325*a(n-24) +3841770422896*a(n-25) -923967990222*a(n-26) -3689384232910*a(n-27) +1300617284437*a(n-28) +2614259101122*a(n-29) -1127033659748*a(n-30) -1366254718948*a(n-31) +660843537364*a(n-32) +524090586634*a(n-33) -269727615782*a(n-34) -146010681184*a(n-35) +76928224259*a(n-36) +28983533038*a(n-37) -15160113967*a(n-38) -3964319226*a(n-39) +2009807783*a(n-40) +352152984*a(n-41) -170267256*a(n-42) -18138336*a(n-43) +8296524*a(n-44) +408240*a(n-45) -176400*a(n-46) for n>48.
Comments