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A075794
a(n) = the least positive integer k such that phi(k) > phi(1) + ... + phi(n).
0
3, 5, 7, 11, 13, 17, 23, 29, 31, 37, 47, 53, 61, 67, 79, 83, 101, 107, 127, 131, 149, 157, 179, 191, 211, 223, 233, 251, 277, 281, 311, 331, 347, 367, 389, 401, 439, 457, 479, 499, 541, 547, 587, 607, 631, 653, 701, 719, 757, 787, 809, 839, 887, 907, 947, 967
OFFSET
1,1
EXAMPLE
phi(1) + ... + phi(4) = 6 and k = 11 is the least positive integer such that sigma(k) > 6. Hence a(4) = 11.
MATHEMATICA
s = 0; a = {}; For[i = 1, i <= 100, i++, s = s + EulerPhi[i]; k = 1; While[EulerPhi[k] <= s, k = k + 1]; a = Append[a, k]]; a
CROSSREFS
Sequence in context: A225526 A090670 A074832 * A192864 A135832 A074781
KEYWORD
nonn
AUTHOR
Joseph L. Pe, Dec 08 2002
STATUS
approved