The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A251344

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A251344

Number of (n+1) X (1+1) 0..2 arrays with every 2 X 2 subblock summing to 3 4 or 5.
(history; published version)

#9 by Bruno Berselli at Thu Nov 29 10:37:04 EST 2018

STATUS

reviewed

approved

#8 by Michel Marcus at Thu Nov 29 05:40:23 EST 2018

STATUS

proposed

reviewed

#7 by Colin Barker at Thu Nov 29 05:27:55 EST 2018

STATUS

editing

proposed

#6 by Colin Barker at Thu Nov 29 05:27:41 EST 2018

NAME

Number of (n+1) X (1+1) 0..2 arrays with every 2X2 2 X 2 subblock summing to 3 4 or 5.

COMMENTS

Column 1 of A251351

FORMULA

Empirical: a(n) = 6*a(n-1) + 3*a(n-2) - 12*a(n-3).

Empirical g.f.: 3*x*(17 + x - 36*x^2) / (1 - 6*x - 3*x^2 + 12*x^3). - Colin Barker, Nov 29 2018

EXAMPLE

Some solutions for n=4:

CROSSREFS

Column 1 of A251351.

STATUS

approved

editing

#5 by R. H. Hardin at Mon Dec 01 19:42:51 EST 2014

STATUS

editing

approved

#4 by R. H. Hardin at Mon Dec 01 19:42:47 EST 2014

LINKS

R. H. Hardin, <a href="/A251344/b251344.txt">Table of n, a(n) for n = 1..210</a>

#3 by R. H. Hardin at Mon Dec 01 19:42:29 EST 2014

NAME

allocated for R. H. Hardin

Number of (n+1)X(1+1) 0..2 arrays with every 2X2 subblock summing to 3 4 or 5

DATA

51, 309, 1899, 11709, 72243, 445797, 2751003, 16976493, 104762403, 646491861, 3989520459, 24619449501, 151927356051, 937548239301, 5785638109947, 35703345104973, 220326406088067, 1359640814523957, 8390383964148267

OFFSET

1,1

COMMENTS

Column 1 of A251351

FORMULA

Empirical: a(n) = 6*a(n-1) +3*a(n-2) -12*a(n-3)

EXAMPLE

Some solutions for n=4

..1..1....0..0....1..1....1..0....1..2....2..1....0..2....1..2....2..1....0..0

..1..0....1..2....1..1....1..1....0..1....0..1....1..0....2..0....2..0....2..2

..2..0....2..0....1..2....1..1....1..2....2..0....2..0....1..0....0..2....1..0

..0..1....0..2....0..1....1..1....2..0....2..0....1..2....2..1....2..1....2..0

..2..2....2..0....2..2....2..0....1..0....0..2....0..1....2..0....0..0....2..1

KEYWORD

allocated

nonn

AUTHOR

R. H. Hardin, Dec 01 2014

STATUS

approved

editing

#2 by R. H. Hardin at Mon Dec 01 19:41:12 EST 2014

KEYWORD

allocating

allocated

#1 by R. H. Hardin at Mon Dec 01 19:41:12 EST 2014

NAME

allocated for R. H. Hardin

KEYWORD

allocating

STATUS

approved