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A082572 a(n) is the least number m such that the arithmetic mean of the distinct primes dividing m equals n. 2
2, 3, 15, 5, 35, 7, 39, 65, 51, 11, 95, 13, 115, 161, 87, 17, 155, 19, 111, 185, 123, 23, 215, 141, 235, 329, 159, 29, 371, 31, 183, 305, 427, 201, 335, 37, 219, 365, 511, 41, 395, 43, 415, 581, 267, 47, 623, 1501, 291, 485, 303, 53, 515, 321, 327, 545, 339, 59 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

COMMENTS

Are there any terms with more than 3 prime factors?

a(p) = p if p is prime. - Paolo P. Lava, Feb 22 2016

LINKS

Paolo P. Lava, Table of n, a(n) for n = 2..1000

EXAMPLE

a(6) = 35 because the prime factors of 35 are {5, 7}, which have mean 6.

MAPLE

with(numtheory): P:= proc(q) local a, b, i, n; for i from 2 to q do

for n from 2 to q do a:=ifactors(n)[2]; b:=add(a[k][1]*a[k][2], k=1..nops(a))/add(a[k][2], k=1..nops(a));

if type(b, integer) then if i=b and mul(a[k][2], k=1..nops(a))=1

then lprint(b, n); break; fi; fi; od; od; end: P(10^9); # Paolo P. Lava, Feb 22 2016

CROSSREFS

Cf. A070009, A078177, A200612.

Sequence in context: A262462 A180698 A266618 * A075244 A088030 A101047

Adjacent sequences:  A082569 A082570 A082571 * A082573 A082574 A082575

KEYWORD

easy,nonn

AUTHOR

David Wasserman, May 06 2003

STATUS

approved

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Last modified May 28 14:47 EDT 2020. Contains 334684 sequences. (Running on oeis4.)