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 A128649 Numbers m such that A128646(m) = A128648(m). 3
 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 14, 15, 16, 17, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 65, 66, 71, 72, 73, 74, 75, 76, 77, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 539, 540, 541, 542, 543, 600, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Terms of this sequence are 1..5, 7..11, 14..17, 21..35, 65..66, 71..77, 81..93, 539..543, 600..639, 644..650, 707..818, 1152..1185, 4502..4577, 4601..4823, 4893..5003, 7483..7633, ... LINKS Table of n, a(n) for n=1..67. Eric Weisstein's World of Mathematics, Prime Sums MATHEMATICA f=0; g=0; Do[p=Prime[n]; f=f+1/(p-1); g=g+(-1)^(n+1)*1/(p-1); kf=Denominator[f]; kg=Denominator[g]; If[Equal[kf, kg], Print[n]], {n, 1, 10000}] CROSSREFS Cf. A128648 (denominator(Sum_{k=1..n} (-1)^(k+1)/(prime(k)-1))). Cf. A128646 (denominator(Sum_{k=1..n} 1/(prime(k)-1))). Cf. A128647, A120271, A119686, A006093, A000040. Sequence in context: A359905 A316465 A004764 * A032894 A032853 A023748 Adjacent sequences: A128646 A128647 A128648 * A128650 A128651 A128652 KEYWORD nonn AUTHOR Alexander Adamchuk, Mar 18 2007 STATUS approved

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Last modified February 22 02:45 EST 2024. Contains 370239 sequences. (Running on oeis4.)