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A109710
Numbers k such that the sum of the digits of pi(k)^prime(k) is divisible by k.
1
1, 10, 35, 63, 106, 153, 602, 1548, 1710, 4680, 5274
OFFSET
1,2
COMMENTS
Next term after 5274 is greater than 10000.
a(12) > 40000. - Jinyuan Wang, Apr 10 2020
EXAMPLE
The digits of pi(1548)^prime(1548) sum to 139320 and 139320 is divisible by 1548, so 1548 is in the sequence.
MATHEMATICA
Do[k = PrimePi[n]^Prime[n]; s = Plus @@ IntegerDigits[k]; If[Mod[s, n] == 0, Print[n]], {n, 1, 10^4}]
PROG
(PARI) is(k) = sumdigits(primepi(k)^prime(k))%k == 0; \\ Jinyuan Wang, Apr 10 2020
CROSSREFS
Cf. A007953.
Sequence in context: A044468 A355491 A351860 * A000447 A052472 A331429
KEYWORD
nonn,base,hard,more
AUTHOR
Ryan Propper, Aug 08 2005
STATUS
approved