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A281560 Number of nX5 0..1 arrays with no element equal to more than two of its horizontal, diagonal or antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1
0, 141, 2426, 12133, 50510, 154722, 430995, 1166392, 3018274, 7606230, 18894693, 46213637, 111557052, 266662314, 631932890, 1486100797, 3471695108, 8062900961, 18628457043, 42837660890, 98091772822, 223754231790, 508613299215 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Column 5 of A281563.
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -7*a(n-2) +10*a(n-3) -38*a(n-4) +37*a(n-5) -5*a(n-6) +94*a(n-7) -20*a(n-8) -167*a(n-9) -113*a(n-10) -134*a(n-11) +498*a(n-12) +330*a(n-13) +105*a(n-14) -507*a(n-15) -927*a(n-16) +72*a(n-17) +503*a(n-18) +953*a(n-19) +224*a(n-20) -809*a(n-21) -464*a(n-22) -161*a(n-23) +378*a(n-24) +441*a(n-25) -162*a(n-26) -189*a(n-27) +27*a(n-28) +27*a(n-29) for n>46
EXAMPLE
Some solutions for n=4
..0..1..1..0..0. .0..1..0..0..1. .0..1..0..0..1. .0..0..1..1..1
..0..0..1..0..1. .0..1..0..0..0. .0..1..0..1..1. .1..0..1..0..0
..1..1..1..0..1. .0..1..0..1..1. .0..1..0..1..1. .0..0..1..0..1
..1..1..0..0..1. .0..1..0..1..0. .1..1..0..1..0. .0..0..1..0..1
CROSSREFS
Cf. A281563.
Sequence in context: A235543 A204469 A201553 * A186955 A005849 A172633
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 24 2017
STATUS
approved

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Last modified March 2 01:29 EST 2024. Contains 370447 sequences. (Running on oeis4.)