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 A120616 Generalized Riordan array (1/sqrt(1+4x^2),(1-sqrt(1+4x^2))/(2x)). 1
 1, 0, -1, -2, 0, 1, 0, 3, 0, -1, 6, 0, -4, 0, 1, 0, -10, 0, 5, 0, -1, -20, 0, 15, 0, -6, 0, 1, 0, 35, 0, -21, 0, 7, 0, -1, 70, 0, -56, 0, 28, 0, -8, 0, 1, 0, -126, 0, 84, 0, -36, 0, 9, 0, -1, -252, 0, 210, 0, -120, 0, 45, 0, -10, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS abs(T(n,k)) is A108044. Product by A007318 is A104505. LINKS FORMULA Number triangle T(n,k)=C(n,(n+k)/2)(-1)^((n+k)/2)(1+(-1)^(n+k))/2 EXAMPLE Triangle begins .1, .0, -1, .-2, 0, 1, .0, 3, 0, -1, .6, 0, -4, 0, 1, .0, -10, 0, 5, 0, -1, .-20, 0, 15, 0, -6, 0, 1, .0, 35, 0, -21, 0, 7, 0, -1, .70, 0, -56, 0, 28, 0, -8, 0, 1, .0, -126, 0, 84, 0, -36, 0, 9, 0, -1, .-252, 0, 210, 0, -120, 0, 45, 0, -10, 0, 1 CROSSREFS Sequence in context: A320602 A134511 A112554 * A108044 A104477 A224928 Adjacent sequences:  A120613 A120614 A120615 * A120617 A120618 A120619 KEYWORD easy,sign,tabl AUTHOR Paul Barry, Jun 17 2006 STATUS approved

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Last modified April 20 06:59 EDT 2021. Contains 343125 sequences. (Running on oeis4.)