A276250 Number of 4Xn 0..2 arrays with no element equal to any value at offset (-2,-1) (-1,1) or (0,-2) and new values introduced in order 0..2.
14, 144, 347, 1447, 6372, 26325, 115682, 509750, 2196820, 9590448, 41943114, 182345942, 794079132, 3464843904, 15086188944, 65723682133, 286477934932, 1248121989813, 5437932782722, 23696963843058, 103252809255037
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..1..1..0. .0..0..1..2. .0..1..1..2. .0..1..2..2. .0..0..1..2 ..2..0..1..1. .1..0..0..2. .2..2..0..0. .0..0..1..1. .2..0..0..1 ..2..2..0..0. .2..2..1..0. .0..1..2..2. .1..2..2..1. .1..2..2..0 ..0..1..2..0. .0..0..2..1. .0..0..1..1. .1..1..2..2. .0..0..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A276248.
Formula
Empirical: a(n) = 2*a(n-1) +16*a(n-2) -5*a(n-3) -96*a(n-4) -140*a(n-5) +637*a(n-6) +1845*a(n-7) -4795*a(n-8) -4911*a(n-9) +12349*a(n-10) -1040*a(n-11) -18997*a(n-12) +57322*a(n-13) +54548*a(n-14) -182018*a(n-15) -172148*a(n-16) +276602*a(n-17) +240887*a(n-18) -309700*a(n-19) -3428*a(n-20) +178083*a(n-21) -246987*a(n-22) -172205*a(n-23) +88525*a(n-24) +1238349*a(n-25) -316382*a(n-26) -1914836*a(n-27) +450326*a(n-28) +1900140*a(n-29) +67773*a(n-30) -2250174*a(n-31) -208550*a(n-32) +2206511*a(n-33) +362321*a(n-34) -1986445*a(n-35) -432077*a(n-36) +1246173*a(n-37) +592283*a(n-38) -611575*a(n-39) -456433*a(n-40) +225504*a(n-41) +147384*a(n-42) +9126*a(n-43) -62519*a(n-44) -16308*a(n-45) +12194*a(n-46) +3502*a(n-47) -600*a(n-48) -251*a(n-49) +286*a(n-50) +69*a(n-51) -134*a(n-52) -27*a(n-53) +19*a(n-54) +8*a(n-55) -a(n-56) -a(n-57) for n>60
Comments