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%I #43 Feb 07 2022 20:17:11
%S 1,1,1,3,1,4,1,5,10,1,6,15,1,7,21,35,1,8,28,56,1,9,36,84,126,1,10,45,
%T 120,210,1,11,55,165,330,462,1,12,66,220,495,792,1,13,78,286,715,1287,
%U 1716,1,14,91,364,1001,2002,3003,1,15,105,455,1365,3003,5005,6435,1,16
%N Triangular array formed from elements to left of middle of Pascal's triangle.
%C Coefficients for Pontryagin classes of projective spaces. See p. 3 of the Wilson link. Aerated to become a lower triangular matrix with alternating zeros on the diagonal, this matrix appparently becomes the reverse, or mirror, of A117178. - _Tom Copeland_, May 30 2017
%H Reinhard Zumkeller, <a href="/A014462/b014462.txt">Rows n = 1..200 of triangle, flattened</a>
%H Jon Maiga, <a href="http://sequencedb.net/s/A014462">Computer-generated formulas for A014462</a>, Sequence Machine.
%H D. Wilson, <a href="http://math.uchicago.edu/~chicagotopology2/cobordism-and-k-theory-talk.pdf">Genera: From cobordism to K-theory</a>, Jul 2016.
%H <a href="/index/Pas#Pascal">Index entries for triangles and arrays related to Pascal's triangle</a>
%e Array begins:
%e 1;
%e 1;
%e 1, 3;
%e 1, 4;
%e 1, 5, 10;
%e 1, 6, 15;
%e 1, 7, 21, 35;
%e 1, 8, 28, 56;
%e 1, 9, 36, 84, 126;
%e 1, 10, 45, 120, 210;
%e 1, 11, 55, 165, 330, 462;
%o (Haskell)
%o a014462 n k = a014462_tabf !! (n-1) !! (k-1)
%o a014462_row n = a014462_tabf !! (n-1)
%o a014462_tabf = map reverse a014413_tabf
%o -- _Reinhard Zumkeller_, Dec 24 2015
%Y Cf. A014413, A034868, A058622 (row sums).
%Y Cf. A001791 (a half-diagonal and diagonal sums).
%Y Cf. A007318, A000037, A008314.
%Y Cf. A117178.
%K tabf,nonn,easy
%O 1,4
%A _Mohammad K. Azarian_
%E More terms from _James A. Sellers_
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