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A251824 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum not 3 or 6 and every diagonal and antidiagonal sum 3 or 6 1
9354, 28202, 130826, 397474, 2395590, 12830794, 38456182, 258040386, 1458543158, 4283605290, 30490194918, 176827937410, 511836962950, 3753133248778, 22033777327254, 63258118796290, 471146262590358, 2783208175723434 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A251829

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +18*a(n-2) +186*a(n-3) -295*a(n-4) -3581*a(n-5) -5476*a(n-6) +27712*a(n-7) +147781*a(n-8) -343417*a(n-9) -664334*a(n-10) +3685778*a(n-11) +11032159*a(n-12) -28166731*a(n-13) -219938272*a(n-14) +169643092*a(n-15) +1244674788*a(n-16) +245160672*a(n-17) -5143057600*a(n-18) -3556473440*a(n-19) +52452832512*a(n-20) -9748484352*a(n-21) -258140220416*a(n-22) -279686815744*a(n-23) +673789935616*a(n-24) +2333219938304*a(n-25) -1555844104192*a(n-26) -3672451776512*a(n-27) -3137051557888*a(n-28) +9117078913024*a(n-29) +4049554374656*a(n-30) -11741526228992*a(n-31) -3800173641728*a(n-32) +3334706561024*a(n-33) +16033649786880*a(n-34) -10475425234944*a(n-35) +11643656339456*a(n-36) -12300786335744*a(n-37) -1649267441664*a(n-38) +1649267441664*a(n-39) for n>42

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A004934 A004954 A004974 * A228519 A292283 A265457

Adjacent sequences:  A251821 A251822 A251823 * A251825 A251826 A251827

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 09 2014

STATUS

approved

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Last modified December 8 03:17 EST 2021. Contains 349590 sequences. (Running on oeis4.)