A280176 Number of nX4 0..1 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
3, 41, 279, 1633, 8759, 43094, 202693, 919058, 4057457, 17554353, 74755040, 314269010, 1307053311, 5386675841, 22025521567, 89442385391, 361014889345, 1449314491017, 5790282988659, 23032601187928, 91257530191537
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..1..1..1. .0..0..0..0. .0..1..1..1. .0..0..1..1. .0..1..1..0 ..0..1..1..0. .0..0..0..0. .0..1..1..1. .0..1..1..0. .0..1..0..0 ..0..1..1..1. .1..1..0..1. .0..0..0..0. .1..0..1..0. .0..0..0..0 ..0..0..1..1. .1..1..0..1. .1..0..0..1. .1..1..1..0. .0..1..0..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A280180.
Formula
Empirical: a(n) = 12*a(n-1) -36*a(n-2) -95*a(n-3) +636*a(n-4) -114*a(n-5) -4112*a(n-6) +3501*a(n-7) +15858*a(n-8) -14979*a(n-9) -50898*a(n-10) +32472*a(n-11) +155801*a(n-12) -45672*a(n-13) -392154*a(n-14) +6334*a(n-15) +749964*a(n-16) +263487*a(n-17) -1160906*a(n-18) -865320*a(n-19) +1407168*a(n-20) +1507520*a(n-21) -1000752*a(n-22) -1913922*a(n-23) +131582*a(n-24) +1715757*a(n-25) +370377*a(n-26) -692041*a(n-27) -487062*a(n-28) -59226*a(n-29) +231552*a(n-30) +194424*a(n-31) -19149*a(n-32) -65094*a(n-33) -26457*a(n-34) -891*a(n-35) +9182*a(n-36) +4908*a(n-37) -726*a(n-38) -746*a(n-39) -222*a(n-40) -24*a(n-41) +60*a(n-42) +12*a(n-43) -9*a(n-44) +a(n-45) for n>54
Comments