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A180765 Half the number of nX5 binary arrays with each element equal to at least one neighbor 1
3, 111, 2385, 52186, 1154119, 25448809, 561487456, 12387396391, 273289411333, 6029284136868, 133017439433103, 2934617106201383, 64743220889823228, 1428358285117311045, 31512293679807784965, 695220984328633501278 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A180771

LINKS

R. H. Hardin, Table of n, a(n) for n=1..199

FORMULA

Empirical: a(n) = 17*a(n-1) + 136*a(n-2) - 345*a(n-3) - 4373*a(n-4) + 71*a(n-5) + 66879*a(n-6) + 73663*a(n-7) - 605750*a(n-8) - 1149380*a(n-9) + 3440076*a(n-10) + 9495118*a(n-11) - 11523196*a(n-12) - 49881727*a(n-13) + 14883216*a(n-14) + 170573727*a(n-15) + 56476212*a(n-16) - 384039937*a(n-17) - 365812542*a(n-18) + 600541982*a(n-19) + 912782329*a(n-20) - 647992787*a(n-21) - 1217873627*a(n-22) + 831099316*a(n-23) + 509861969*a(n-24) - 535317645*a(n-25) - 243113473*a(n-26) + 146477582*a(n-27) + 239475023*a(n-28) - 56646215*a(n-29) - 153066695*a(n-30) + 13721643*a(n-31) + 55901473*a(n-32) + 8739700*a(n-33) - 17235985*a(n-34) - 7556526*a(n-35) + 4435220*a(n-36) + 2967912*a(n-37) - 742411*a(n-38) - 903018*a(n-39) + 68146*a(n-40) + 206458*a(n-41) + 20454*a(n-42) - 27768*a(n-43) - 10964*a(n-44) + 1696*a(n-45) + 1408*a(n-46)

CROSSREFS

Sequence in context: A114738 A111091 A301612 * A232769 A066138 A114207

Adjacent sequences:  A180762 A180763 A180764 * A180766 A180767 A180768

KEYWORD

nonn

AUTHOR

R. H. Hardin Sep 20 2010

STATUS

approved

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Last modified December 2 08:31 EST 2021. Contains 349437 sequences. (Running on oeis4.)