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A262844 Number of (n+2)X(2+2) 0..1 arrays with each row divisible by 7 and column not divisible by 7, read as a binary number with top and left being the most significant bits. 1
6, 34, 132, 396, 1264, 3962, 11886, 35914, 108556, 325668, 976552, 2931922, 8795766, 26370674, 79104084, 237312252, 711756448, 2135076202, 6405228606, 19214238554, 57640739420, 172922218260, 518757049560, 1556255741762, 4668767225286 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A262849.

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) -4*a(n-2) +20*a(n-3) -68*a(n-4) +68*a(n-5) -162*a(n-6) +444*a(n-7) -444*a(n-8) +644*a(n-9) -1244*a(n-10) +1244*a(n-11) -1277*a(n-12) +1376*a(n-13) -1376*a(n-14) +1032*a(n-15)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Cf. A262849.

Sequence in context: A061616 A222308 A166812 * A166941 A086934 A009469

Adjacent sequences:  A262841 A262842 A262843 * A262845 A262846 A262847

KEYWORD

nonn

AUTHOR

R. H. Hardin, Oct 03 2015

STATUS

approved

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Last modified December 10 05:49 EST 2018. Contains 318044 sequences. (Running on oeis4.)