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A074632 Sum of first, 2nd, 3rd, 4th and 5th powers of divisors of n are divisible by sum of divisors of n. 0
1, 20, 64, 500, 729, 1024, 1280, 4096, 4352, 14580, 15625, 32000, 39168, 46656, 47360, 59049, 65536, 117649, 144640, 161024, 262144, 312500, 364500, 509184, 531441, 746496, 796797, 933120, 1000000, 1180980, 1184000, 1449216, 1771561 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

n=20: s1=42,s2=546=13.42,s3=9198=219.42,s4=170898=4069.42, s5=3304182=78671.42

MATHEMATICA

Select[Range[2000000], And@@Divisible[DivisorSigma[Range[2, 5], #], DivisorSigma[ 1, #]]&] (* Harvey P. Dale, Jan 01 2012 *)

CROSSREFS

See also A020487, A046841, A046870, A046871.

Cf. A000203, A001157-A001160.

Sequence in context: A262486 A187156 A246877 * A225190 A228839 A158444

Adjacent sequences:  A074629 A074630 A074631 * A074633 A074634 A074635

KEYWORD

easy,nonn

AUTHOR

Labos Elemer, Aug 27 2002

STATUS

approved

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Last modified December 13 00:17 EST 2017. Contains 295954 sequences.