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 A173279 Irregular triangle read by rows: M(n,k) = (n-2*k)!, k=0..floor(n/2). 2
 1, 1, 2, 1, 6, 1, 24, 2, 1, 120, 6, 1, 720, 24, 2, 1, 5040, 120, 6, 1, 40320, 720, 24, 2, 1, 362880, 5040, 120, 6, 1, 3628800, 40320, 720, 24, 2, 1, 39916800, 362880, 5040, 120, 6, 1, 479001600, 3628800, 40320, 720, 24, 2, 1, 6227020800, 39916800, 362880, 5040, 120, 6, 1, 87178291200 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS In the limit as j-> infinity, the power M^j approaches the limit described in A173280. Row sums: sum_{k=0..n/2} M(n,k) = A136580(n). LINKS EXAMPLE Triangle starts in row n=0 as: 1; 1; 2, 1; 6, 1; 24, 2, 1; 120, 6, 1; 720, 24, 2, 1; 5040, 120, 6, 1; 40320, 720, 24, 2, 1; 362880, 5040, 120, 6, 1; 3628800, 40320, 720, 24, 2, 1; 39916800, 362880, 5040, 120, 6, 1; 479001600, 3628800, 40320, 720, 24, 2, 1; ... MAPLE A173279 := proc(n, k) factorial(n-2*k) ; end proc: seq(seq(A173279(n, k), k=0..floor(n/2)), n=0..20) ; # R. J. Mathar, Feb 22 2010 CROSSREFS Cf. A000142, A136580, A173280 Sequence in context: A279095 A186283 A307374 * A277440 A321597 A083720 Adjacent sequences:  A173276 A173277 A173278 * A173280 A173281 A173282 KEYWORD nonn,tabf AUTHOR Gary W. Adamson, Feb 14 2010 EXTENSIONS keyword tabl replaced by tabf, R. J. Mathar, Feb 22 2010 STATUS approved

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Last modified May 9 04:59 EDT 2021. Contains 343687 sequences. (Running on oeis4.)