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A187933 Number of (n+2)X4 binary arrays with every 2X2 subblock sum equal to some diagonal or antidiagonal neighbor 2X2 subblock sum 1
44, 104, 704, 2532, 14308, 64024, 328116, 1509288, 7610052, 36481660, 180534736, 869511316, 4284355448, 20864250924, 102391000452, 498989985620, 2445651060392, 11953995167792, 58540364415804, 286162414812456 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A187940

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..200

FORMULA

Empirical: a(n)=8*a(n-1)-18*a(n-2)+6*a(n-3)+304*a(n-4)-2033*a(n-5)+4034*a(n-6)-580*a(n-7)-28763*a(n-8)+151699*a(n-9)-282467*a(n-10)+50276*a(n-11)+1173373*a(n-12)-4810771*a(n-13)+8448909*a(n-14)-3832537*a(n-15)-19145259*a(n-16)+77277253*a(n-17)-139216499*a(n-18)+106280857*a(n-19)+128969780*a(n-20)-686066310*a(n-21)+1332354155*a(n-22)-1320546548*a(n-23)-134214361*a(n-24)+3430781392*a(n-25)-7447681464*a(n-26)+8649852375*a(n-27)-3263437890*a(n-28)-8740672240*a(n-29)+23870214560*a(n-30)-32193286295*a(n-31)+21921745920*a(n-32)+3625661685*a(n-33)-39628520857*a(n-34)+67737879788*a(n-35)-62712514658*a(n-36)+35408423577*a(n-37)+20487107016*a(n-38)-71671379796*a(n-39)+83259647444*a(n-40)-82639430156*a(n-41)+25055626404*a(n-42)+26357815576*a(n-43)-46896528420*a(n-44)+76959675332*a(n-45)-26100705884*a(n-46)+4069895120*a(n-47)+20658712264*a(n-48)-52895629880*a(n-49)-4230213968*a(n-50)-4064870912*a(n-51)-37012235712*a(n-52)+52432794368*a(n-53)+4199264480*a(n-54)+11271623520*a(n-55)+34228002752*a(n-56)-30018029504*a(n-57)+2026068352*a(n-58)-6677852672*a(n-59)-13614194432*a(n-60)+3580450816*a(n-61)-2653281024*a(n-62)-4018797568*a(n-63)+6763790336*a(n-64)-1936586240*a(n-65)+197451776*a(n-66)+1509737472*a(n-67)-927522816*a(n-68)+739151872*a(n-69)-182849536*a(n-70)+103931904*a(n-71)+10715136*a(n-72)+27918336*a(n-73)-8323072*a(n-74)+3670016*a(n-75)

EXAMPLE

Some solutions for 6X4

..1..0..0..0....0..1..0..0....0..1..0..0....0..0..1..1....0..1..0..1

..0..0..1..0....1..0..1..1....0..0..0..1....1..1..0..0....1..1..1..1

..1..0..0..0....0..1..0..0....0..1..0..1....0..0..1..1....0..1..0..1

..0..0..1..0....0..1..1..1....0..1..0..0....1..1..0..0....0..0..0..0

..1..0..0..0....1..1..0..1....1..0..1..0....0..0..1..1....0..1..0..1

..0..0..1..0....0..1..1..1....1..0..0..1....1..1..0..0....0..0..0..0

CROSSREFS

Sequence in context: A253391 A050944 A332590 * A118483 A044231 A044612

Adjacent sequences:  A187930 A187931 A187932 * A187934 A187935 A187936

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 16 2011

STATUS

approved

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Last modified December 9 05:30 EST 2021. Contains 349627 sequences. (Running on oeis4.)