login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A207074
Number of 7Xn 0..1 arrays avoiding 0 0 1 and 0 1 0 horizontally and 0 0 1 and 1 0 1 vertically
1
14, 196, 966, 4536, 24304, 111426, 468348, 1992996, 8204200, 32364700, 126207438, 485459784, 1829249768, 6809144730, 25110435922, 91539487000, 330608108182, 1185426647902, 4218712592850, 14911669509057, 52409625818926
OFFSET
1,1
COMMENTS
Row 7 of A207068
LINKS
FORMULA
Empirical: a(n) = 13*a(n-1) -77*a(n-2) +383*a(n-3) -1936*a(n-4) +7922*a(n-5) -28256*a(n-6) +103017*a(n-7) -335295*a(n-8) +972967*a(n-9) -2898437*a(n-10) +7966108*a(n-11) -19695289*a(n-12) +50590479*a(n-13) -121311483*a(n-14) +261567751*a(n-15) -598810479*a(n-16) +1278613877*a(n-17) -2435180257*a(n-18) +5103796480*a(n-19) -9830453100*a(n-20) +16639266482*a(n-21) -32810735226*a(n-22) +57338491218*a(n-23) -86327093442*a(n-24) +165368021800*a(n-25) -261215742290*a(n-26) +348609720526*a(n-27) -675060737155*a(n-28) +947076002811*a(n-29) -1114104267547*a(n-30) +2291266909445*a(n-31) -2752950138758*a(n-32) +2846776029030*a(n-33) -6591178122692*a(n-34) +6378804191029*a(n-35) -5860717529743*a(n-36) +16246332680119*a(n-37) -11492394343561*a(n-38) +9831250373548*a(n-39) -34372580178341*a(n-40) +15047096292563*a(n-41) -13775536083585*a(n-42) +62011759601185*a(n-43) -11209722202073*a(n-44) +16941038227703*a(n-45) -94239166030921*a(n-46) -4304990908984*a(n-47) -19443731342848*a(n-48) +118797207702512*a(n-49) +27461057092152*a(n-50) +21121113946208*a(n-51) -122114528749824*a(n-52) -45290805108400*a(n-53) -20290807770736*a(n-54) +100417788663552*a(n-55) +46418065916544*a(n-56) +15492754380096*a(n-57) -64466394516288*a(n-58) -32418504516096*a(n-59) -8453846568960*a(n-60) +31216358866176*a(n-61) +15231769369344*a(n-62) +2924248780800*a(n-63) -10776946268160*a(n-64) -4459567104000*a(n-65) -474099609600*a(n-66) +2364899328000*a(n-67) +658409472000*a(n-68) -268738560000*a(n-70)
EXAMPLE
Some solutions for n=4
..1..0..1..1....0..0..0..0....1..0..0..0....0..1..1..1....0..1..1..1
..1..0..0..0....1..0..0..0....1..0..0..0....1..1..0..0....1..1..1..1
..1..0..0..0....1..0..0..0....0..0..0..0....1..1..0..0....1..1..1..1
..0..0..0..0....0..0..0..0....0..0..0..0....1..0..0..0....1..1..1..1
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....1..1..1..1
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..1..1..1
..0..0..0..0....0..0..0..0....0..0..0..0....0..0..0..0....0..1..1..0
CROSSREFS
Sequence in context: A207963 A207502 A209654 * A207407 A207708 A207253
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 14 2012
STATUS
approved