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A325570
Numbers n that have no divisor d > 1 such that A048720(A065621(d),n/d) = n.
6
1, 3, 5, 7, 11, 13, 15, 17, 19, 23, 25, 27, 29, 31, 37, 39, 41, 43, 47, 51, 53, 55, 57, 59, 61, 63, 67, 69, 71, 73, 77, 79, 81, 83, 85, 87, 89, 91, 95, 97, 99, 101, 103, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 131, 137, 139, 141, 143, 145, 147, 149, 151, 157, 159, 163, 167, 169, 171, 173, 175, 177, 179, 181
OFFSET
1,2
LINKS
PROG
(PARI)
A048720(b, c) = fromdigits(Vec(Pol(binary(b))*Pol(binary(c)))%2, 2);
A065621(n) = bitxor(n-1, n+n-1);
isA325570(n) = fordiv(n, d, if(A048720(A065621(n/d), d)==n, return(d==n)));
CROSSREFS
Positions of ones in A325565 and A325566.
Cf. A065091 (a subsequence), A325571 (the composite terms), A325572 (complement).
Subsequence of A005408 (odd numbers).
Sequence in context: A152955 A235866 A334141 * A210719 A353685 A322840
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 10 2019
STATUS
approved