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 A081291 Complement of A072795. 25
 0, 3, 6, 7, 8, 14, 15, 16, 17, 18, 19, 20, 21, 22, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS This gives positions of those terms in A063171 which begin with digits 11... Also the elements of table A072764 which do not occur in the leftmost column. See the comment at A081292. LINKS FORMULA a(0)=0, a(n) = n + A014137(A081288(n)-1). a(n) = A080300(A081292(n)) = A081289(n) + n - A081290(n). PROG (PARI) A014137(n) = sum(k=0, n, binomial(2*k, k)/(k+1); ); A081288(n) = my(i=0); while(binomial(2*i, i)/(i+1) <= n, i++); i; a(n) = if (n==0, 0,  n + A014137(A081288(n)-1)); \\ Michel Marcus, Apr 28 2020 CROSSREFS Cf. A072795, A014137, A081288. Cf. A080300, A081289, A081290, A081292. Sequence in context: A189098 A241007 A139451 * A189095 A188968 A189211 Adjacent sequences:  A081288 A081289 A081290 * A081292 A081293 A081294 KEYWORD nonn AUTHOR Antti Karttunen, Mar 17 2003 STATUS approved

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Last modified July 28 00:54 EDT 2021. Contains 346316 sequences. (Running on oeis4.)