The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A280809 Number of nX7 0..1 arrays with no element equal to more than two of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1
 0, 1047, 24490, 133067, 521862, 1736603, 5219491, 14672850, 39446188, 102668319, 261032587, 651872767, 1605291205, 3909190755, 9432062891, 22579858190, 53688882185, 126896063565, 298328702932, 698005209403, 1626059718118 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Column 7 of A280810. LINKS R. H. Hardin, Table of n, a(n) for n = 1..151 FORMULA Empirical: a(n) = 13*a(n-1) -72*a(n-2) +220*a(n-3) -400*a(n-4) +432*a(n-5) -256*a(n-6) +64*a(n-7) +6*a(n-8) -54*a(n-9) +183*a(n-10) -249*a(n-11) -51*a(n-12) +573*a(n-13) -672*a(n-14) +264*a(n-15) +33*a(n-16) +39*a(n-17) -156*a(n-18) +12*a(n-19) +225*a(n-20) -57*a(n-21) -390*a(n-22) +402*a(n-23) -19*a(n-24) -173*a(n-25) +66*a(n-26) +126*a(n-27) -156*a(n-28) +33*a(n-30) +93*a(n-31) -96*a(n-32) +2*a(n-33) +43*a(n-34) -45*a(n-35) -20*a(n-36) +74*a(n-37) -30*a(n-38) -18*a(n-39) +15*a(n-40) -3*a(n-41) -9*a(n-42) +15*a(n-43) -3*a(n-44) -3*a(n-45) -a(n-48) +a(n-49) for n>60 EXAMPLE Some solutions for n=4 ..0..1..0..0..1..0..1. .0..1..0..0..1..1..0. .0..0..1..0..0..1..0 ..1..1..1..0..1..0..1. .0..1..0..1..0..1..1. .1..1..0..1..0..1..0 ..0..0..1..0..1..0..1. .1..0..0..1..0..0..0. .0..1..0..1..0..1..0 ..1..1..0..1..0..0..1. .1..1..1..0..1..1..0. .1..1..0..1..0..1..1 CROSSREFS Cf. A280810. Sequence in context: A226114 A249653 A056092 * A252307 A236273 A251375 Adjacent sequences: A280806 A280807 A280808 * A280810 A280811 A280812 KEYWORD nonn AUTHOR R. H. Hardin, Jan 08 2017 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified February 25 06:40 EST 2024. Contains 370310 sequences. (Running on oeis4.)