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 A177994 Triangle read by rows, A177990 * A070909 3
 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 3, 1, 2, 1, 1, 3, 1, 2, 1, 1, 1, 4, 1, 3, 1, 2, 1, 1, 4, 1, 3, 1, 2, 1, 1, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Row sums = A101881: (1, 2, 4, 5, 8, 9, 13, 14,...). LINKS Reinhard Zumkeller, Rows n = 0..100 of triangle, flattened FORMULA As infinite lower triangular matrices, A177990 * A070909 EXAMPLE First few rows of the triangle = 1; 1, 1; 2, 1, 1; 2, 1, 1, 1; 3, 1, 2, 1, 1; 3, 1, 2, 1, 1, 1; 4, 1, 3, 1, 2, 1, 1; 4, 1, 3, 1, 2, 1, 1, 1; 5, 1, 4, 1, 3, 1, 2, 1, 1; 5, 1, 4, 1, 3, 1, 2, 1, 1, 1; 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1; 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 1; 7, 1, 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1; 7, 1, 6, 1, 5, 1, 4, 1, 3, 1, 2, 1, 1, 1; ... PROG (Haskell) a177994 n k = a177994_tabl !! n !! k a177994_row n = a177994_tabl !! n a177994_tabl = [1] : [1, 1] : map f a177994_tabl                where f xs@(x:_) = (x + 1) : 1 : xs -- Reinhard Zumkeller, Feb 20 2015 CROSSREFS Cf. A177991 = A070909 * A177990. Cf. A101881. Sequence in context: A273619 A034003 A168508 * A179285 A026835 A117975 Adjacent sequences:  A177991 A177992 A177993 * A177995 A177996 A177997 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, May 16 2010 STATUS approved

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Last modified February 16 19:49 EST 2019. Contains 320167 sequences. (Running on oeis4.)