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A325572 Numbers n that have divisor d > 1 such that A048720(A065621(d),n/d) = n. 3
2, 4, 6, 8, 9, 10, 12, 14, 16, 18, 20, 21, 22, 24, 26, 28, 30, 32, 33, 34, 35, 36, 38, 40, 42, 44, 45, 46, 48, 49, 50, 52, 54, 56, 58, 60, 62, 64, 65, 66, 68, 70, 72, 74, 75, 76, 78, 80, 82, 84, 86, 88, 90, 92, 93, 94, 96, 98, 100, 102, 104, 105, 106, 108, 110, 112, 114, 116, 118, 120, 122, 124, 126, 128, 129, 130, 132, 133 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Equally, numbers n such that there exists natural numbers t > 1 and u >= 1, for which A048720(t,u) = n and A065620(t)*u = n.
LINKS
PROG
(PARI)
A048720(b, c) = fromdigits(Vec(Pol(binary(b))*Pol(binary(c)))%2, 2);
A065621(n) = bitxor(n-1, n+n-1);
isA325572(n) = fordiv(n, d, if(A048720(A065621(n/d), d)==n, return(d<n)));
CROSSREFS
Cf. A048720, A065620, A065621, A325570 (complement).
Union of A005843 (without zero) and A325573 (odd terms).
Sequence in context: A336375 A353683 A296214 * A337945 A247423 A182339
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 10 2019
STATUS
approved

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Last modified April 18 10:01 EDT 2024. Contains 371779 sequences. (Running on oeis4.)