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A358222
Composite numbers k such that A003415(k) divides A276086(k), where A003415 is the arithmetic derivative, and A276086 is the primorial base exp-function.
3
6, 9, 21, 25, 26, 33, 38, 46, 49, 65, 77, 94, 141, 146, 161, 185, 201, 206, 207, 209, 221, 305, 321, 326, 333, 341, 346, 375, 377, 406, 413, 453, 458, 531, 581, 589, 605, 615, 689, 717, 741, 745, 746, 766, 819, 869, 893, 965, 989, 1041, 1046, 1073, 1189, 1241, 1254, 1331, 1337, 1349, 1461, 1466, 1469, 1529, 1541, 1641
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); };
A358220(n) = if(n<2, 0, !(A276086(n)%A003415(n)));
isA358222(n) = (!isprime(n)&&A358220(n));
CROSSREFS
Composite terms in A358221.
Sequence in context: A376472 A357840 A355484 * A165717 A239874 A043103
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 23 2022
STATUS
approved