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%I #12 Feb 15 2016 12:17:12
%S 1,1,3,1,4,1,10,5,1,15,6,1,35,21,7,1,56,28,8,1,126,84,36,9,1,210,120,
%T 45,10,1,462,330,165,55,11,1,792,495,220,66,12,1,1716,1287,715,286,78,
%U 13,1,3003,2002,1001,364,91,14,1,6435,5005,3003,1365,455,105,15,1
%N Triangular array formed from elements to right of middle of Pascal's triangle.
%H Reinhard Zumkeller, <a href="/A014413/b014413.txt">Rows n = 1..200 of triangle, flattened</a>
%e 1;
%e 1;
%e 3, 1;
%e 4, 1;
%e 10, 5, 1;
%e 15, 6, 1;
%e 35, 21, 7, 1;
%e 56, 28, 8, 1;
%e 126, 84, 36, 9, 1;
%e 210, 120, 45, 10, 1;
%e 462, 330, 165, 55, 11, 1;
%e 792, 495, 220, 66, 12, 1.
%o (Haskell)
%o a014413 n k = a014413_tabf !! (n-1) !! (k-1)
%o a014413_row n = a014413_tabf !! (n-1)
%o a014413_tabf = [1] : f 1 [1] where
%o f 0 us'@(_:us) = ys : f 1 ys where
%o ys = zipWith (+) us' (us ++ [0])
%o f 1 vs@(v:_) = ys' : f 0 ys where
%o ys@(_:ys') = zipWith (+) (vs ++ [0]) ([v] ++ vs)
%o -- _Reinhard Zumkeller_, Dec 24 2015
%Y Cf. A014462.
%Y Cf. A007318, A034868, A034869, A265848.
%K tabf,nonn,easy
%O 1,3
%A _Mohammad K. Azarian_
%E More terms from _James A. Sellers_
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