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A007626 Sum of divisors of superabundant numbers (A004394). 5
1, 3, 7, 12, 28, 60, 91, 124, 168, 360, 546, 744, 1170, 2418, 2880, 4368, 5952, 9360, 19344, 39312, 59520, 99944, 112320, 232128, 471744, 714240, 1199328, 1451520, 2437344, 2926080, 3249792, 6604416, 9999360 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Local maxima of sigma(n), the sum of divisors function A000203.

Same as A063072 for the first 19 terms. - T. D. Noe, Jul 01 2008

LINKS

T. D. Noe, Table of n, a(n) for n=1..500

MATHEMATICA

Reap[ For[ n=1; a=0, n <= 3*10^6, n++, s = DivisorSigma[1, n]; b = s/n; If[ b>a, a=b; Print[s]; Sow[s]]]][[2, 1]] (* Jean-Fran├žois Alcover, Apr 02 2013 *)

CROSSREFS

Cf. A002192, A000203, A051444, A004394.

See A034885 and A002093 for another version.

Sequence in context: A256259 A182941 A063072 * A193297 A240738 A047068

Adjacent sequences:  A007623 A007624 A007625 * A007627 A007628 A007629

KEYWORD

nonn,easy,nice

AUTHOR

Walter Nissen

STATUS

approved

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Last modified June 26 15:16 EDT 2017. Contains 288766 sequences.