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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A175685 Array a(n,m) = Sum_{j=floor((n-1)/2)-m..floor(n-1)/2} binomial(n-j-1,j) read by antidiagonals.

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%I A175685 #15 May 12 2019 02:22:48
%S A175685 1,1,1,1,1,1,2,2,1,1,1,3,2,1,1,3,4,3,2,1,1,1,7,5,3,2,1,1,4,7,8,5,3,2,
%T A175685 1,1,1,14,12,8,5,3,2,1,1
%N A175685 Array a(n,m) = Sum_{j=floor((n-1)/2)-m..floor(n-1)/2} binomial(n-j-1,j) read by antidiagonals.
%C A175685 A102426 defines an array of binomials in which partial sums of row n yield row a(n,.).
%D A175685 Burton, David M., Elementary number theory, McGraw Hill, N.Y., 2002, p. 286.
%e A175685 a(n,m) starts in row n=1 as
%e A175685   1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1, ...
%e A175685   1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1, ...
%e A175685   1,  2,  2,  2,  2,  2,  2,  2,  2,  2,  2, ...
%e A175685   2,  3,  3,  3,  3,  3,  3,  3,  3,  3,  3, ...
%e A175685   1,  4,  5,  5,  5,  5,  5,  5,  5,  5,  5, ...
%e A175685   3,  7,  8,  8,  8,  8,  8,  8,  8,  8,  8, ...
%e A175685   1,  7, 12, 13, 13, 13, 13, 13, 13, 13, 13, ...
%e A175685   4, 14, 20, 21, 21, 21, 21, 21, 21, 21, 21, ...
%e A175685   1, 11, 26, 33, 34, 34, 34, 34, 34, 34, 34, ...
%p A175685 A175685 := proc(n,m) upl := floor( (n-1)/2) ; add( binomial(n-j-1,j),j=upl-m .. upl) ; end proc: # _R. J. Mathar_, Dec 05 2010
%t A175685 a = Table[Table[Sum[Binomial[n -j - 1, j], {j, Floor[(n - 1)/2] - m, Floor[(n - %t 1)/2]}], {n, 0, 10}], {m, 0, 10}];
%t A175685 Table[Table[a[[m, n - m + 1]], {m, 1, n - 1}], {n, 1, 10}];Flatten[%]
%Y A175685 Cf. A000045, A011973, A102426.
%K A175685 nonn,tabl,easy
%O A175685 1,7
%A A175685 _Roger L. Bagula_, Dec 04 2010