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 A242653 Triangle read by rows: T(n,k) = ((n+k)/2)!/k! if n,k have same parity, otherwise 0. 1
 1, 0, 1, 1, 0, 1, 0, 2, 0, 1, 2, 0, 3, 0, 1, 0, 6, 0, 4, 0, 1, 6, 0, 12, 0, 5, 0, 1, 0, 24, 0, 20, 0, 6, 0, 1, 24, 0, 60, 0, 30, 0, 7, 0, 1, 0, 120, 0, 120, 0, 42, 0, 8, 0, 1, 120, 0, 360, 0, 210, 0, 56, 0, 9, 0, 1, 0, 720, 0, 840, 0, 336, 0, 72, 0, 10, 0, 1, 720, 0, 2520, 0, 1680, 0, 504, 0, 90, 0, 11, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,8 LINKS Robert Israel, Table of n, a(n) for n = 0..10010 Alexander Kreinin, Combinatorial Properties of Mills' Ratio, arXiv:1405.5852, 2014. See Table 4. EXAMPLE Triangle begins: 1 0 1 1 0 1 0 2 0 1 2 0 3 0 1 0 6 0 4 0 1 6 0 12 0 5 0 1 0 24 0 20 0 6 0 1 ... MAPLE N:= 1000; # to get a(0) to a(N) count:= -1; for n from 0 while count < N do   for k from 0 to n while count  < N do     count:= count+1;     if type(n-k, even) then        A[count]:= ((n+k)/2)!/k!     else        A[count]:= 0     fi;   od od: seq(A[i], i=0..N); # Robert Israel, Jun 10 2014 MATHEMATICA Table[If[EvenQ[n-k], ((n+k)/2)!/k!, 0], {n, 0, 12}, {k, 0, n}] // Flatten (* Jean-François Alcover, Sep 19 2018 *) CROSSREFS Sequence in context: A322378 A053121 A113408 * A191530 A321435 A173863 Adjacent sequences:  A242650 A242651 A242652 * A242654 A242655 A242656 KEYWORD nonn,tabl,easy AUTHOR N. J. A. Sloane, May 29 2014 STATUS approved

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Last modified January 17 16:39 EST 2019. Contains 319235 sequences. (Running on oeis4.)