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A251904 Number of (n+2)X(7+2) 0..3 arrays with every 3X3 subblock row and column sum unequal to 4 or 5 and every diagonal and antidiagonal sum equal to 4 or 5 1
23868, 9830, 16848, 28288, 101508, 202792, 325504, 1183404, 2519780, 4658222, 15724032, 35357236, 72617464, 229816136, 549341468, 1254019770, 3754851816, 9453776420, 23234277672, 66855509068, 174358076576, 450572667250 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A251905

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 2*a(n-1) +3*a(n-3) +40*a(n-4) -69*a(n-5) +138*a(n-6) -360*a(n-7) -475*a(n-8) +215*a(n-9) -4975*a(n-10) +8810*a(n-11) -1237*a(n-12) +14194*a(n-13) +56223*a(n-14) -64765*a(n-15) +66490*a(n-16) -144412*a(n-17) -230720*a(n-18) +162909*a(n-19) -506611*a(n-20) +665377*a(n-21) +270448*a(n-22) +98311*a(n-23) +1978807*a(n-24) -2185960*a(n-25) +160649*a(n-26) -844446*a(n-27) -4411980*a(n-28) +4586609*a(n-29) -636232*a(n-30) +951905*a(n-31) +4783626*a(n-32) -4033624*a(n-33) +3079735*a(n-34) -2957559*a(n-35) -3133445*a(n-36) +2599794*a(n-37) -3664596*a(n-38) +2770680*a(n-39) +43410*a(n-40) -168774*a(n-41) +1943130*a(n-42) -1491672*a(n-43) +782664*a(n-44) -379728*a(n-45) -279360*a(n-46) +275856*a(n-47) -269616*a(n-48) +148992*a(n-49) -41472*a(n-50) -3072*a(n-51) +12288*a(n-52) -9216*a(n-53) +3072*a(n-54) for n>58

EXAMPLE

Some solutions for n=4

..1..2..0..1..0..1..0..2..1....2..1..3..2..3..2..3..2..3

..0..3..0..3..0..3..0..3..0....3..0..3..0..3..0..3..0..3

..2..3..1..3..2..3..1..3..2....1..0..2..0..1..0..2..0..1

..1..0..2..0..1..0..2..0..1....2..3..1..3..2..3..1..3..2

..3..0..3..0..3..0..3..0..3....0..3..0..3..0..3..0..3..0

..2..2..3..2..3..2..3..1..3....1..2..0..1..1..1..0..1..0

CROSSREFS

Sequence in context: A332313 A237691 A185991 * A239177 A204359 A224620

Adjacent sequences:  A251901 A251902 A251903 * A251905 A251906 A251907

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 10 2014

STATUS

approved

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Last modified November 27 20:49 EST 2021. Contains 349395 sequences. (Running on oeis4.)