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A355002
Numbers k that share a prime factor with A355456(k).
2
135, 140, 285, 435, 455, 675, 700, 855, 885, 910, 945, 980, 1120, 1185, 1305, 1335, 1365, 1425, 1435, 1485, 1540, 1635, 1755, 1820, 1995, 2085, 2175, 2235, 2275, 2295, 2380, 2565, 2574, 2655, 2660, 2685, 2870, 2905, 2985, 3045, 3105, 3135, 3185, 3220, 3311, 3375, 3395, 3435, 3500, 3555, 3585, 3640, 3705, 3915, 4005
OFFSET
1,1
COMMENTS
Numbers k such that A324198(k) and A342671(k) are not relatively prime.
PROG
(PARI)
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A355442(n) = gcd(A003961(n), A276086(n));
A355456(n) = gcd(sigma(n), A355442(n));
isA355002(n) = (1!=gcd(n, A355456(n)));
CROSSREFS
Subsequence of A324584 and of A349166.
Sequence in context: A374536 A371307 A335950 * A038369 A066282 A235809
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 13 2022
STATUS
approved