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A060434
An inverse to Mertens's function: smallest k >= 2 such that Mertens's function |M(k)| (see A002321) is equal to n.
4
2, 3, 5, 13, 31, 110, 114, 197, 199, 443, 659, 661, 665, 1105, 1106, 1109, 1637, 2769, 2770, 2778, 2791, 2794, 2795, 2797, 2802, 2803, 6986, 6987, 7013, 7021, 8503, 8506, 8507, 8509, 8510, 8511, 9749, 9822, 9823, 9830, 9831, 9833, 9857, 9861, 19043
OFFSET
0,1
COMMENTS
Related to the Riemann Hypothesis through the Titchmarsh Theorem.
EXAMPLE
M(1637) = 17 because the sum of Moebius mu(1) + mu(2) + ... + mu(1637) = 17.
MAPLE
with(numtheory): k := -1: s := 0: for n from 1 to 20000 do s := s+mobius(n): if (abs(s) > k) and (n>1) then k := abs(s): print(n, k); fi; od:
MATHEMATICA
Reap[ For[ k = -1; s = 0; n = 1, n <= 20000, n++, s = s + MoebiusMu[n]; If[Abs[s] > k && n > 1, k = Abs[s]; Sow[n]]]][[2, 1]] (* Jean-François Alcover, Sep 04 2013, after Maple *)
CROSSREFS
Essentially same as A051402 except for initial terms.
Sequence in context: A167495 A041519 A355512 * A072999 A175093 A342180
KEYWORD
nonn,nice
AUTHOR
Luis Rodriguez-Torres (ludovicusmagister(AT)yahoo.com), Apr 06 2001
STATUS
approved