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A365422
Numbers k for which k and A163511(k) have the same prime signature.
3
3, 6, 7, 12, 14, 24, 28, 31, 45, 48, 55, 56, 62, 90, 96, 110, 111, 112, 119, 123, 124, 127, 175, 180, 192, 207, 220, 222, 224, 238, 246, 247, 248, 253, 254, 350, 360, 384, 414, 440, 444, 447, 448, 476, 492, 494, 496, 506, 508, 567, 700, 720, 768, 828, 880, 888, 894, 895, 896, 927, 945, 952, 957, 959, 984, 987, 988, 992
OFFSET
1,1
COMMENTS
If k is present, then 2*k is also a term, and vice versa.
PROG
(PARI)
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
A163511(n) = if(!n, 1, my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
A365421(n) = (A046523(A163511(n))==A046523(n));
isA365422(n) = A365421(n);
CROSSREFS
Cf. A046523, A163511, A278531, A365421 (characteristic function).
Subsequences: A007283, A335431, A365423 (odd terms).
Sequence in context: A022434 A242666 A226228 * A335431 A269174 A161903
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 04 2023
STATUS
approved