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A340091
Odd numbers k such that A064989(k) is in A340151.
3
679, 703, 1387, 1729, 1891, 2047, 2509, 2701, 2821, 3277, 3367, 5551, 7471, 7735, 8119, 8827, 9997, 10963, 11305, 12403, 13021, 13747, 13981, 14491, 14701, 15841, 16471, 17563, 19951, 21349, 21907, 21931, 22015, 23959, 24727, 25669, 26281, 27511, 28939, 29341, 31417, 32407, 38503, 39091, 39831, 39865, 40501, 41041
OFFSET
1,1
COMMENTS
Sequence A003961(A340151(i)), for i >= 1, sorted into ascending order.
By definition, this has no common terms with A340077 nor any of its subsequences like A339869 or A339880.
LINKS
PROG
(PARI)
A000265(n) = (n>>valuation(n, 2));
A003961(n) = { my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A339904(n) = A000265(eulerphi(A003961(n)));
A340075(n) = { my(u=A339904(n)); u/gcd(A003961(n)-1, u); };
A247074(n) = { my(f=factor(n)); eulerphi(f)/prod(i=1, #f~, gcd(f[i, 1]-1, n-1)); }; \\ From A247074
isA340151(n) = ((1!=A340075(n))&&(1==A340149(n)));
A064989(n) = { my(f=factor(n)); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f) };
isA340091(n) = ((n%2)&&isA340151(A064989(n)));
CROSSREFS
Cf. A340092 (Carmichael numbers in this sequence).
Sequence in context: A046514 A199995 A352263 * A374556 A164650 A200828
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 31 2020
STATUS
approved