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A257355 Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum equal to the antidiagonal sum or central row sum less than the central column sum 1

%I #4 Apr 20 2015 13:50:37

%S 784,2116,6724,20449,53824,145924,451584,1368900,3724900,10240000,

%T 30603024,90897156,253892356,710862244,2085383556,6110861584,

%U 17291198016,48919707684,142124476036,413163557284,1177385585476,3351857932864

%N Number of (n+2)X(2+2) 0..1 arrays with no 3x3 subblock diagonal sum equal to the antidiagonal sum or central row sum less than the central column sum

%C Column 2 of A257361

%H R. H. Hardin, <a href="/A257355/b257355.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 5*a(n-2) +2*a(n-3) +53*a(n-4) +12*a(n-5) -230*a(n-6) -72*a(n-7) -463*a(n-8) -144*a(n-9) +1301*a(n-10) +170*a(n-11) -1891*a(n-12) -1004*a(n-13) +16562*a(n-14) -748*a(n-15) -186*a(n-16) +5100*a(n-17) -2028*a(n-18) +11416*a(n-19) +16030*a(n-20) +35640*a(n-21) -362906*a(n-22) +277568*a(n-23) +114785*a(n-24) +160612*a(n-25) -1868387*a(n-26) +1107206*a(n-27) +814413*a(n-28) +1376008*a(n-29) -5531494*a(n-30) +1143960*a(n-31) +1612833*a(n-32) +5633280*a(n-33) -8273387*a(n-34) -856522*a(n-35) -38781*a(n-36) +10065296*a(n-37) -3435092*a(n-38) -1561924*a(n-39) -2018936*a(n-40) +6596304*a(n-41) +3880456*a(n-42) -174080*a(n-43) -1021152*a(n-44) -1480896*a(n-45) +897952*a(n-46) -1210624*a(n-47) -983712*a(n-48) -1478016*a(n-49) -653440*a(n-50) +296896*a(n-51) +467328*a(n-52) +862208*a(n-53) +413056*a(n-54) +134656*a(n-55) -120576*a(n-56) -237056*a(n-57) -135936*a(n-58) -97792*a(n-59) +15104*a(n-60) +38912*a(n-61) +39936*a(n-62) +18432*a(n-63) -4096*a(n-64) -4096*a(n-65) -4096*a(n-66) for n>68

%e Some solutions for n=4

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

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

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

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

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

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

%Y Cf. A257361

%K nonn

%O 1,1

%A _R. H. Hardin_, Apr 20 2015

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Last modified April 23 11:35 EDT 2024. Contains 371912 sequences. (Running on oeis4.)