

A098002


Sum of squares of distinct prime divisors p of n, where each p <= sqrt(n).


3



0, 0, 0, 4, 0, 4, 0, 4, 9, 4, 0, 13, 0, 4, 9, 4, 0, 13, 0, 4, 9, 4, 0, 13, 25, 4, 9, 4, 0, 38, 0, 4, 9, 4, 25, 13, 0, 4, 9, 29, 0, 13, 0, 4, 34, 4, 0, 13, 49, 29, 9, 4, 0, 13, 25, 53, 9, 4, 0, 38, 0, 4, 58, 4, 25, 13, 0, 4, 9, 78, 0, 13, 0, 4, 34, 4, 49, 13, 0, 29, 9, 4, 0, 62, 25, 4, 9, 4, 0, 38, 49
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OFFSET

1,4


LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000


EXAMPLE

2 and 3 are the distinct prime divisors of 12 and both 2 and 3 are <= sqrt(12), so a(12) = 2^2 + 3^2 = 13.


MATHEMATICA

ssdpd[n_]:=Total[Select[Transpose[FactorInteger[n]][[1]], #<=Sqrt[n]&]^2]; Join[{0}, Array[ssdpd, 90, 2]] (* Harvey P. Dale, Mar 11 2013 *)


PROG

(PARI) a(n) = sumdiv(n, d, isprime(d)*(d^2<=n)*d^2); \\ Michel Marcus, Dec 22 2017


CROSSREFS

Cf. A097974.
Sequence in context: A035673 A035638 A292142 * A241658 A256719 A343722
Adjacent sequences: A097999 A098000 A098001 * A098003 A098004 A098005


KEYWORD

nonn


AUTHOR

Leroy Quet, Sep 08 2004


EXTENSIONS

More terms from John W. Layman, Sep 14 2004


STATUS

approved



