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A325573
Odd numbers n that have divisor d > 1 such that A048720(A065621(d),n/d) = n.
3
9, 21, 33, 35, 45, 49, 65, 75, 93, 105, 129, 133, 135, 153, 155, 161, 165, 189, 195, 217, 225, 259, 273, 279, 297, 309, 315, 341, 345, 381, 385, 403, 441, 465, 513, 525, 527, 561, 567, 585, 589, 597, 611, 621, 635, 645, 651, 681, 693, 705, 713, 729, 765, 775, 793, 819, 837, 889, 899, 945, 961, 1025, 1029, 1035, 1057, 1065
OFFSET
1,1
LINKS
PROG
(PARI)
A048720(b, c) = fromdigits(Vec(Pol(binary(b))*Pol(binary(c)))%2, 2);
A065621(n) = bitxor(n-1, n+n-1);
isA325573(n) = ((n%2)&&fordiv(n, d, if(A048720(A065621(n/d), d)==n, return(d<n))));
CROSSREFS
Subsequence of A071904 and of A325572.
Sequence in context: A110701 A243703 A133929 * A086470 A176256 A017629
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 10 2019
STATUS
approved