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A251843 Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime 1

%I #4 Dec 09 2014 15:57:59

%S 1951,5438,21748,48692,277125,1226031,2726048,16168331,74290304,

%T 163730464,998856517,4693337366,10286321048,63845445267,303868751600,

%U 663861257682,4160750200373,19942932871102,43493338467394

%N Number of (n+2)X(6+2) 0..3 arrays with every 3X3 subblock row and column sum nonprime and every diagonal and antidiagonal sum prime

%C Column 6 of A251845

%H R. H. Hardin, <a href="/A251843/b251843.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 123*a(n-3) -4692*a(n-6) +69631*a(n-9) -514311*a(n-12) +2250027*a(n-15) -6529710*a(n-18) +13126892*a(n-21) -18315243*a(n-24) +17438687*a(n-27) -11035045*a(n-30) +4492984*a(n-33) -1153262*a(n-36) +193456*a(n-39) -19536*a(n-42) for n>50

%e Some solutions for n=4

%e ..1..1..2..1..1..2..1..1....1..1..2..1..1..2..1..1....3..0..1..0..0..1..0..3

%e ..0..0..1..0..0..1..0..0....0..0..1..0..0..1..0..0....1..1..2..1..1..2..1..1

%e ..0..3..1..0..0..1..0..0....3..0..1..0..0..1..0..3....0..3..1..0..0..1..0..0

%e ..1..1..2..1..1..2..1..1....1..1..2..1..1..2..1..1....0..0..1..3..0..1..0..3

%e ..0..0..1..0..0..1..0..3....0..0..1..0..0..1..0..0....1..1..2..1..1..2..1..1

%e ..0..0..1..3..0..1..3..0....3..0..1..0..0..1..0..0....3..0..1..0..0..1..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 09 2014

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Last modified August 11 09:55 EDT 2024. Contains 375059 sequences. (Running on oeis4.)