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A065432 Triangle related to Catalan triangle: recurrence related to A033877 (Schroeder numbers). 2
1, 1, -1, 1, -2, 0, 1, -3, 1, 1, 1, -4, 3, 2, 0, 1, -5, 6, 2, -2, -2, 1, -6, 10, 0, -6, -4, 0, 1, -7, 15, -5, -11, -3, 5, 5, 1, -8, 21, -14, -15, 4, 15, 10, 0, 1, -9, 28, -28, -15, 19, 26, 6, -14, -14, 1, -10, 36, -48, -7, 42, 30, -16, -42, -28, 0, 1, -11, 45, -75, 14, 70, 16, -60, -70, -14, 42, 42, 1, -12, 55, -110, 54, 96, -28, -120 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Sums of odd rows are 0, of even rows are the Catalan numbers (A000108) with alternating signs. Row sums of unsigned version give A065441.

LINKS

Table of n, a(n) for n=0..85.

FORMULA

a[0, 0] := 1; a[n_, k_] := 0/;(k > n||n < 0||k < 0); a[n_, k_] := a[n, k] = a[n, k-1]-2a[n-1, k-1]+a[n-1, k]; Table[a[n, k], {n, 0, 16}, {k, 0, n}]

EXAMPLE

{1},{1,-1},{1,-2,0},{1,-3,1,1},{1,-4,3,2,0}

CROSSREFS

Sequence in context: A168532 A181940 A093555 * A094184 A078805 A122837

Adjacent sequences:  A065429 A065430 A065431 * A065433 A065434 A065435

KEYWORD

sign

AUTHOR

Wouter Meeussen, Nov 16 2001

STATUS

approved

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Last modified April 23 19:18 EDT 2014. Contains 240946 sequences.