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A212863 Numbers n such that the sum of prime factors of n (counted with multiplicity) equals five times the largest prime divisor. 0
32, 192, 216, 243, 3125, 3750, 4000, 4500, 4800, 5120, 5400, 5760, 6075, 6480, 7290, 16807, 24010, 28812, 34300, 41160, 43904, 46305, 49000, 49392, 55125, 55566, 58800, 62720, 65625, 66150, 70000, 70560, 75264, 78750, 79380, 84000, 84672, 89600, 94500, 95256 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The numbers prime(n)^5 are in the sequence.

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

192 is in the sequence because 192 = 2^6 * 3 => sum of prime divisors = 2*6 + 3 = 15 = 5*3 where 3 is the greatest prime divisor.

MAPLE

with(numtheory):A:= proc(n) local e, j; e := ifactors(n)[2]: add (e[j][1]*e[j][2], j=1..nops(e)) end: for m from 2 to 500000 do: x:=factorset(m):n1:=nops(x):if A(m)=5*x[n1] then printf(`%d, `, m):else fi:od:

CROSSREFS

Cf. A001414, A163836, A212861, A212862.

Sequence in context: A233387 A200840 A208925 * A019560 A130811 A232051

Adjacent sequences:  A212860 A212861 A212862 * A212864 A212865 A212866

KEYWORD

nonn

AUTHOR

Michel Lagneau, May 29 2012

STATUS

approved

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Last modified December 7 17:09 EST 2016. Contains 278888 sequences.