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 A130503 a(n) = denominator of the sum of reciprocals of those positive integers which are <= n and are not among the first (n-1) terms of A130502. 2
 1, 2, 6, 12, 12, 4, 28, 56, 504, 2520, 27720, 27720, 27720, 27720, 5544, 11088, 188496, 62832, 1193808, 5969040, 1989680, 1989680, 45762640, 137287920, 686439600, 8923714800, 80313433200, 80313433200, 2329089562800, 2329089562800 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Diana Mecum, Table of n, a(n) for n = 1..200 EXAMPLE The positive integers which are <= 9 and are missing from the first 8 terms of the (numerator) sequence A130502 are 2,3,4,6,7,8,9. So a(9) is the denominator of (1/2 +1/3 +1/4 +1/6 +1/7 +1/8 + 1/9 = 821/504). CROSSREFS Cf. A130502. Sequence in context: A009230 A069491 A127698 * A278232 A074385 A057340 Adjacent sequences:  A130500 A130501 A130502 * A130504 A130505 A130506 KEYWORD frac,nonn AUTHOR Leroy Quet, May 31 2007 EXTENSIONS More terms from Diana L. Mecum, Jun 14 2007 STATUS approved

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Last modified June 18 04:41 EDT 2021. Contains 345098 sequences. (Running on oeis4.)