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 A223835 Number of n X 5 0..1 arrays with rows and antidiagonals unimodal and columns nondecreasing. 1
 16, 86, 255, 596, 1240, 2388, 4325, 7436, 12222, 19316, 29499, 43716, 63092, 88948, 122817, 166460, 221882, 291348, 377399, 482868, 610896, 764948, 948829, 1166700, 1423094, 1722932, 2071539, 2474660, 2938476, 3469620, 4075193, 4762780, 5540466 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 5 of A223838. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = (2/15)*n^5 + (1/6)*n^4 + (19/6)*n^3 + (28/3)*n^2 + (126/5)*n - 36 for n>2. Conjectures from Colin Barker, Aug 23 2018: (Start) G.f.: x*(16 - 10*x - 21*x^2 + 36*x^3 + 9*x^4 - 18*x^5 + 2*x^6 + 2*x^7) / (1 - x)^6. a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>8. (End) EXAMPLE Some solutions for n=3: ..1..0..0..0..0....1..1..1..0..0....1..0..0..0..0....0..1..1..0..0 ..1..1..1..1..0....1..1..1..0..0....1..1..1..1..0....1..1..1..1..1 ..1..1..1..1..1....1..1..1..1..0....1..1..1..1..0....1..1..1..1..1 CROSSREFS Cf. A223838. Sequence in context: A223962 A252834 A050256 * A224143 A225007 A070052 Adjacent sequences:  A223832 A223833 A223834 * A223836 A223837 A223838 KEYWORD nonn AUTHOR R. H. Hardin, Mar 27 2013 STATUS approved

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Last modified October 19 15:50 EDT 2019. Contains 328223 sequences. (Running on oeis4.)