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A358228
Numbers k such that A276086(k) mod A003415(k) is an odd number, where A003415 is the arithmetic derivative and A276086 is the primorial base exp-function.
6
4, 8, 10, 12, 14, 16, 20, 22, 24, 28, 30, 32, 36, 40, 42, 44, 48, 50, 52, 54, 56, 58, 60, 62, 63, 64, 66, 68, 72, 74, 75, 76, 78, 80, 84, 88, 90, 92, 96, 98, 99, 100, 102, 104, 108, 110, 112, 114, 116, 120, 122, 124, 126, 128, 132, 136, 138, 140, 144, 148, 150, 152, 154, 156, 158, 160, 162, 164, 168, 171, 172, 176
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);
isA358228(n) = A358227(n);
CROSSREFS
Complement: {1} U A358229.
Cf. A003415, A276086, A328382, A358228 (characteristic function), A358232 (subsequence).
Cf. also A358225.
Sequence in context: A172458 A175226 A057166 * A230854 A377035 A360668
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 25 2022
STATUS
approved