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 A026571 a(n)=T(n,n-2), T given by A026568. Also a(n) = number of integer strings s(0),...,s(n) counted by T, such that s(n)=2. 0
 1, 2, 7, 16, 44, 106, 273, 672, 1696, 4214, 10573, 26392, 66151, 165578, 415277, 1041480, 2615004, 6568450, 16512355, 41531360, 104526093, 263206638, 663143211, 1671581968, 4215574482, 10635988422, 26846320149, 67790042264 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,2 LINKS FORMULA Conjecture: (n+2)*a(n) +3*(-n-1)*a(n-1) -3*n*a(n-2) +11*(n-1)*a(n-3) +2*(n-6)*a(n-4) +4*(-2*n+7)*a(n-5)=0. - R. J. Mathar, Jun 23 2013 CROSSREFS Sequence in context: A113224 A178945 A309561 * A100099 A164267 A184352 Adjacent sequences:  A026568 A026569 A026570 * A026572 A026573 A026574 KEYWORD nonn AUTHOR STATUS approved

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Last modified December 10 14:27 EST 2019. Contains 329896 sequences. (Running on oeis4.)