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A371085
Nonsquarefree numbers k such that A003415(k) divides A276086(k), where A003415 is the arithmetic derivative, and A276086 is the primorial base exp-function.
3
9, 25, 49, 207, 333, 375, 531, 605, 819, 1331, 1719, 1850, 2057, 2205, 2299, 2331, 2853, 4491, 4575, 5746, 6413, 6591, 6655, 9559, 9873, 12947, 13426, 14063, 15851, 15886, 16425, 17303, 19125, 19942, 20531, 21609, 21970, 22139, 26667, 30923, 33975, 34731, 35379, 37251, 37873, 38350, 38599, 39075, 41743, 44447, 45950
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)));
isA371085(n) = (!issquarefree(n)&&A358220(n));
CROSSREFS
Intersection of A013929 and A358221 (or A358222).
Subsequence of A371083, and of A371086.
Sequence in context: A112629 A225322 A031162 * A362971 A348232 A147160
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 12 2024
STATUS
approved