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 A113680 Riordan array ((1-x-2x^2)/(1-x),x). 2
 1, 0, 1, -2, 0, 1, -2, -2, 0, 1, -2, -2, -2, 0, 1, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, -2, -2, -2, -2, -2, 0, 1, -2, -2, -2, -2, -2, -2, -2, -2 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Inverse of A113678. Sequence array of A113679. Row sums are 3-2n-2*0^n. Diagonal sums are 1-n. LINKS FORMULA Number triangle T(n, k)=if(k<=n, C(0, n-k)+2*C(1, n-k)-2, 0). EXAMPLE Triangle begins 1; 0, 1; -2, 0, 1; -2, -2, 0, 1; -2, -2, -2, 0, 1; -2, -2, -2, -2, 0, 1; CROSSREFS Sequence in context: A101663 A284749 A062169 * A316723 A128187 A266477 Adjacent sequences:  A113677 A113678 A113679 * A113681 A113682 A113683 KEYWORD easy,sign,tabl AUTHOR Paul Barry, Nov 04 2005 STATUS approved

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Last modified August 25 05:45 EDT 2019. Contains 326323 sequences. (Running on oeis4.)