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 A239040 Number of n X 1 0..3 arrays with no element equal to one plus the sum of elements to its left or one plus the sum of elements above it, modulo 4. 3
 3, 7, 16, 38, 90, 212, 500, 1180, 2784, 6568, 15496, 36560, 86256, 203504, 480128, 1132768, 2672544, 6305344, 14876224, 35097536, 82805760, 195363968, 460923008, 1087457536, 2565643008, 6053132032, 14281179136, 33693644288, 79493552640 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 1 of A239047. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 2*a(n-1) + 2*a(n-3). Empirical g.f.: x*(3 + x + 2*x^2) / (1 - 2*x - 2*x^3). - Colin Barker, Feb 24 2018 EXAMPLE Some solutions for n=5: ..0....3....2....3....0....0....2....2....2....0....2....3....3....0....0....3 ..2....2....0....2....0....0....0....2....0....3....0....2....2....2....2....3 ..0....3....0....3....0....0....0....3....0....2....2....0....0....2....0....2 ..0....0....0....0....0....3....2....3....2....3....0....3....0....0....2....3 ..0....3....0....2....3....2....3....2....2....3....0....0....3....0....2....2 CROSSREFS Cf. A239047. Sequence in context: A192665 A052967 A297498 * A323225 A293065 A211278 Adjacent sequences:  A239037 A239038 A239039 * A239041 A239042 A239043 KEYWORD nonn AUTHOR R. H. Hardin, Mar 09 2014 STATUS approved

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Last modified September 16 06:21 EDT 2019. Contains 327090 sequences. (Running on oeis4.)