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 A211103 a(n) is 1/4 the number of (n+1) X (n+1) 0..3 symmetric matrices with every 2 X 2 subblock having one or three distinct values. 0
 7, 121, 5011, 493189, 116069407, 65255935753, 87660979427131, 281363248472730805, 2157777098414728716343, 39538807262703057593016241 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE Some solutions for n=3: 1 2 0 3 2 3 2 0 3 1 3 2 3 2 1 1 1 1 2 2 2 0 1 1 3 0 3 2 1 2 3 0 2 1 0 3 1 1 3 0 0 1 2 0 2 3 1 2 3 3 1 0 1 0 2 3 2 3 0 1 3 1 0 1 0 2 2 0 2 0 0 2 1 3 3 1 2 0 1 2 CROSSREFS Sequence in context: A094088 A012043 A316730 * A012103 A012086 A074487 Adjacent sequences: A211100 A211101 A211102 * A211104 A211105 A211106 KEYWORD nonn,more AUTHOR R. H. Hardin, Mar 31 2012 STATUS approved

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Last modified March 28 06:07 EDT 2023. Contains 361577 sequences. (Running on oeis4.)