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A227679 T(n,k)=Number of nXk 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X(k+1) binary array having an odd sum, with rows and columns of the latter in lexicographically nondecreasing order 6
2, 4, 4, 7, 16, 7, 11, 50, 50, 11, 16, 131, 283, 131, 16, 22, 301, 1343, 1343, 301, 22, 29, 625, 5434, 11971, 5434, 625, 29, 37, 1198, 19188, 90884, 90884, 19188, 1198, 37, 46, 2153, 60484, 592791, 1330361, 592791, 60484, 2153, 46, 56, 3670, 173433, 3380440 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

..2....4......7.......11..........16............22..............29

..4...16.....50......131.........301...........625............1198

..7...50....283.....1343........5434.........19188...........60484

.11..131...1343....11971.......90884........592791.........3380440

.16..301...5434....90884.....1330361......16795263.......184000783

.22..625..19188...592791....16795263.....418147052......9062032214

.29.1198..60484..3380440...184000783....9062032214....392636087774

.37.2153.173433.17161921..1773503344..172087530120..14928759496120

.46.3670.459198.78807477.15261176700.2897975481614.502146361367093

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..144

FORMULA

Empirical for column k:

k=1: a(n) = (1/2)*n^2 + (1/2)*n + 1

k=2: [polynomial of degree 6]

k=3: [polynomial of degree 14]

k=4: [polynomial of degree 30]

k=5: [polynomial of degree 62]

EXAMPLE

Some solutions for n=4 k=4

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

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

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

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

CROSSREFS

Column 1 is A000124

Sequence in context: A223644 A223637 A223620 * A223782 A223716 A188607

Adjacent sequences:  A227676 A227677 A227678 * A227680 A227681 A227682

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Jul 19 2013

STATUS

approved

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Last modified October 22 21:09 EDT 2018. Contains 316505 sequences. (Running on oeis4.)