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A065390 Peak values reached by A062402 at the sites listed in A065389. 2
1, 3, 7, 12, 18, 28, 31, 39, 42, 56, 72, 91, 96, 98, 168, 195, 252, 280, 312, 360, 372, 392, 546, 576, 744, 840, 864, 992, 1092, 1170, 1344, 1512, 1680, 1860, 1872, 2016, 2240, 2418, 2880, 3224, 3600, 3844, 4320, 4368, 4914, 5082, 5952, 6045, 6552, 7440 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..500

MATHEMATICA

a=0; s=0; Do[s=DivisorSigma[1, EulerPhi[n]]; If[s>a, a=s; Print[s]], {n, 1, 10000}]

(* Second program: *)

Union@ FoldList[Max, Array[DivisorSigma[1, EulerPhi[#]] &, 2200]] (* Michael De Vlieger, Jun 19 2018 *)

PROG

(PARI) { n=r=0; for (m=1, 10^9, x=sigma(eulerphi(m)); if (x > r, r=x; write("b065390.txt", n++, " ", x); if (n==500, return)) ) } \\ Harry J. Smith, Oct 18 2009

CROSSREFS

Cf. A062402, A000203, A000010, A065389, A065391, A065392, A065393, A065394.

Sequence in context: A184534 A109638 A008332 * A171835 A324125 A212293

Adjacent sequences:  A065387 A065388 A065389 * A065391 A065392 A065393

KEYWORD

nonn

AUTHOR

Labos Elemer, Nov 05 2001

STATUS

approved

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Last modified July 17 08:40 EDT 2019. Contains 325097 sequences. (Running on oeis4.)