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A183637 Number of (n+1) X 5 0..3 arrays with every 2 X 2 subblock summing to 6. 1
1576, 2884, 6136, 14644, 38056, 105604, 309016, 945364, 3004936, 9877924, 33458296, 116413684, 414874216, 1510107844, 5598165976, 21077667604, 80389277896, 309840123364, 1204303904056, 4712234595124, 18534372807976 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A183642.

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) - 35*a(n-2) + 50*a(n-3) - 24*a(n-4).

Conjectures from Colin Barker, Mar 31 2018: (Start)

G.f.: 4*x*(394 - 3219*x + 8114*x^2 - 6144*x^3) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)).

a(n) = 570 + 45*2^(3+n) + 10*3^(2+n) + 4^(1+n).

(End)

EXAMPLE

Some solutions for 3 X 5:

  2 1 2 0 2      2 1 2 2 2      3 0 3 0 1      3 2 3 2 3

  3 0 3 1 3      0 3 0 2 0      0 3 0 3 2      0 1 0 1 0

  2 1 2 0 2      3 0 3 1 3      3 0 3 0 1      2 3 2 3 2

CROSSREFS

Cf. A183642.

Sequence in context: A203087 A278559 A263525 * A223399 A210294 A203961

Adjacent sequences:  A183634 A183635 A183636 * A183638 A183639 A183640

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 06 2011

STATUS

approved

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Last modified July 11 17:24 EDT 2020. Contains 335626 sequences. (Running on oeis4.)