A206653 Number of (n+2)X4 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically or nw-to-se diagonally exactly two ways, and new values 0..1 introduced in row major order

390, 1769, 8374, 39928, 190577, 910169, 4345011, 20745372, 99072051, 473072354, 2258928115, 10786845653, 51508637025, 245959541842, 1174491287887, 5608355555142, 26780628595266, 127881076950311, 610649258608125

Offset

1,1

Comments

Column 2 of A206659

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 6*a(n-2) +70*a(n-3) +111*a(n-4) +11*a(n-5) -1038*a(n-6) -2212*a(n-7) -1228*a(n-8) +6222*a(n-9) +14947*a(n-10) +4864*a(n-11) -21444*a(n-12) -37809*a(n-13) +37708*a(n-14) +69192*a(n-15) -16620*a(n-16) -247948*a(n-17) -181648*a(n-18) +265738*a(n-19) +294365*a(n-20) -25710*a(n-21) -311918*a(n-22) +1014729*a(n-23) +1556509*a(n-24) -3780019*a(n-25) -6949650*a(n-26) -2669749*a(n-27) +16905404*a(n-28) +19548332*a(n-29) -4383804*a(n-30) -36037146*a(n-31) -30507685*a(n-32) +15475748*a(n-33) +43855826*a(n-34) +30266708*a(n-35) -13081195*a(n-36) -21467990*a(n-37) -16915949*a(n-38) +7498639*a(n-39) +2382846*a(n-40) -6646771*a(n-41) +22164150*a(n-42) -20152361*a(n-43) -372616*a(n-44) -19073865*a(n-45) +18150630*a(n-46) +4473011*a(n-47) -14909593*a(n-48) +1916272*a(n-49) -15127805*a(n-50) +20327817*a(n-51) +1517558*a(n-52) -6955067*a(n-53) -6298662*a(n-54) +7138737*a(n-55) +6828905*a(n-56) -5259661*a(n-57) +1095788*a(n-58) +569873*a(n-59) +859792*a(n-60) +1148261*a(n-61) +401017*a(n-62) +1545245*a(n-63) +1189595*a(n-64) +590643*a(n-65) -31467*a(n-66) -26637*a(n-67) +275467*a(n-68) +196219*a(n-69) +198819*a(n-70) +39906*a(n-71) -32890*a(n-72) +32129*a(n-73) +8601*a(n-74) -1306*a(n-75) +613*a(n-76) -1805*a(n-77) -174*a(n-78) -1197*a(n-79) +21*a(n-80) +378*a(n-81) -27*a(n-82) for n>85

Example

Some solutions for n=4
..0..1..0..0....0..0..0..1....0..0..0..0....0..1..0..0....0..1..1..1
..1..0..1..0....1..1..1..1....0..1..1..0....0..1..0..0....1..0..0..0
..0..0..0..0....0..0..1..1....1..1..1..1....1..1..0..1....0..0..0..1
..1..0..1..1....1..0..1..0....1..1..0..0....0..1..0..1....0..0..1..1
..0..0..1..1....1..1..1..1....1..0..0..0....1..1..0..0....0..1..1..1
..0..0..0..1....0..0..0..0....0..0..0..1....1..1..1..1....1..1..1..0

Crossrefs

Sequence in context: A069477 A325993 A108573 * A202429 A236612 A332419

Adjacent sequences: A206650 A206651 A206652 * A206654 A206655 A206656

Keyword

nonn

Author

R. H. Hardin Feb 11 2012

Status

approved