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A341044
Numbers k such that A318996(k) is prime.
1
8, 9, 10, 14, 15, 21, 22, 25, 26, 33, 34, 39, 42, 46, 57, 62, 65, 66, 69, 72, 74, 76, 80, 82, 87, 91, 92, 93, 94, 95, 100, 106, 111, 116, 119, 121, 122, 129, 133, 134, 145, 146, 159, 162, 166, 172, 176, 177, 183, 184, 190, 194, 202, 203, 206, 208, 213, 214, 215, 219, 232, 236, 237, 238, 240, 243
OFFSET
1,1
COMMENTS
Contains 2*p for p in A023201 and 3*p for p in A023203.
LINKS
EXAMPLE
a(3) = 10 is a term because A318996(10) = 11 is prime.
MAPLE
f:= proc(n) local s, D, t;
D:= numtheory:-divisors(n);
s:= convert(D, `+`);
add(s mod t, t=D)
end proc:
select(t -> isprime(f(t)), [$1..1000]);
PROG
(PARI) f(n) = my(sn = sigma(n)); sumdiv(n, d, sn % d); \\ A318996
isok(k) = isprime(f(k)); \\ Michel Marcus, Feb 04 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Feb 03 2021
STATUS
approved