A251917 - OEIS

%I #4 Dec 11 2014 06:34:48

%S 1914,3054,4624,4938,10704,19964,34396,76834,157770,319716,740790,

%T 1685004,3846896,9112670,21481768,50721208,121511664,290632366,

%U 695789488,1673868150,4026097838,9684997378,23347339456,56274247106,135653112384

%N Number of (n+2)X(2+2) 0..3 arrays with every 3X3 subblock row and column sum 2 4 5 or 7 and every diagonal and antidiagonal sum not 2 4 5 or 7

%C Column 2 of A251923

%H R. H. Hardin, <a href="/A251917/b251917.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +32*a(n-3) -47*a(n-4) -23*a(n-5) -440*a(n-6) +343*a(n-7) +642*a(n-8) +3413*a(n-9) +588*a(n-10) -7308*a(n-11) -16536*a(n-12) -25667*a(n-13) +41740*a(n-14) +52393*a(n-15) +186768*a(n-16) -102638*a(n-17) -105643*a(n-18) -689747*a(n-19) -128440*a(n-20) +65369*a(n-21) +1280423*a(n-22) +1603575*a(n-23) +539189*a(n-24) -136708*a(n-25) -4265738*a(n-26) -2604698*a(n-27) -5150241*a(n-28) +2997077*a(n-29) +5332802*a(n-30) +12333661*a(n-31) +9336476*a(n-32) -2405377*a(n-33) -12409108*a(n-34) -25817624*a(n-35) -12305820*a(n-36) -78297*a(n-37) +24743640*a(n-38) +27867445*a(n-39) +16214136*a(n-40) -2916474*a(n-41) -23518833*a(n-42) -20986543*a(n-43) -13970868*a(n-44) +3704091*a(n-45) +11763865*a(n-46) +11754761*a(n-47) +7138800*a(n-48) -719074*a(n-49) -3128378*a(n-50) -4425844*a(n-51) -2624296*a(n-52) -792382*a(n-53) +406114*a(n-54) +1223686*a(n-55) +928430*a(n-56) +403224*a(n-57) -190568*a(n-58) -324084*a(n-59) -148672*a(n-60) +6344*a(n-61) +50496*a(n-62) +19952*a(n-63) +480*a(n-64) -2880*a(n-65) -960*a(n-66) for n>69

%e Some solutions for n=4

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

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 11 2014