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A358229
Numbers k such that A276086(k) mod A003415(k) is an even number, where A003415 is the arithmetic derivative and A276086 is the primorial base exp-function.
5
2, 3, 5, 6, 7, 9, 11, 13, 15, 17, 18, 19, 21, 23, 25, 26, 27, 29, 31, 33, 34, 35, 37, 38, 39, 41, 43, 45, 46, 47, 49, 51, 53, 55, 57, 59, 61, 65, 67, 69, 70, 71, 73, 77, 79, 81, 82, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 101, 103, 105, 106, 107, 109, 111, 113, 115, 117, 118, 119, 121, 123, 125, 127, 129, 130, 131
OFFSET
1,1
PROG
(PARI)
A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A358227(n) = ((A276086(n)%A003415(n))%2);
isA358229(n) = !A358227(n);
CROSSREFS
Complement: {1} U A358228.
Cf. A003415, A276086, A328382, A358221 (subsequence), A358227 (characteristic function).
Cf. also A358226.
Sequence in context: A349150 A354525 A340610 * A106843 A057165 A245395
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 25 2022
STATUS
approved