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A033852 Integers k such that j(k)*phi(k) = sigma(k), where j(n) = A033831(n). 0
35, 105, 248, 418, 594, 744, 812, 1254 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(9) > 10^7. - Michel Marcus, Nov 05 2014
a(9) > 10^8. - Manfred Scheucher, May 30 2015
LINKS
PROG
(PARI) isok(n) = sumdiv(n, d, (d>=3) && (q=n/d) && (q>=1) && (q<=d-2))*eulerphi(n) == sigma(n); \\ Michel Marcus, Nov 05 2014
CROSSREFS
Cf. A000010 (phi), A000203 (sigma), A033831.
Sequence in context: A015882 A347384 A010085 * A241610 A183854 A156332
KEYWORD
more,nonn
AUTHOR
STATUS
approved

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Last modified July 21 13:28 EDT 2024. Contains 374474 sequences. (Running on oeis4.)