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A112822 Least number k such that lcm{1,2,...,k}/denominator of harmonic number H(k) = 2n-1. 10
1, 6, 105, 44, 63, 33, 156, 20, 272, 343, 38272753, 11881, 100, 66, 822, 28861, 77 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

First occurrence of 2n-1 in A110566.

Sequence continues: a(18)=?, 1332, 162, 2758521, 24649, 21, a(24)=?, 294, a(26)=?, 1166, 110, 126059, 201957, 3660, 37553041

LINKS

Table of n, a(n) for n=1..17.

MATHEMATICA

a = h = 1; t = Table[0, {100}]; Do[a = LCM[a, n]; h = h + 1/n; b = a/Denominator[h]; If[b < 101 && t[[(b + 1)/2]] == 0, t[[(b + 1)/2]] = n], {n, 500000}]; t

CROSSREFS

Cf. A110566, A098464, A112813, A112814, A112815, A112816, A112817, A112818, A112819, A112820, A112821.

Sequence in context: A055969 A285027 A184188 * A033589 A077289 A279520

Adjacent sequences:  A112819 A112820 A112821 * A112823 A112824 A112825

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Sep 15 2005

EXTENSIONS

a(11), a(32) from Max Alekseyev, Nov 29 2013

STATUS

approved

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Last modified August 18 22:17 EDT 2018. Contains 313840 sequences. (Running on oeis4.)