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URL: https://oeis.org/A391738

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A391738
Numbers k such that 25*k = A048720(41, k), where A048720 is carryless base-2 multiplication.
5
0, 31, 62, 63, 93, 95, 124, 125, 126, 127, 186, 190, 191, 248, 250, 252, 253, 254, 255, 372, 380, 381, 382, 383, 496, 500, 504, 506, 508, 509, 510, 511, 744, 760, 762, 764, 765, 766, 767, 992, 1000, 1008, 1012, 1016, 1018, 1020, 1021, 1022, 1023, 1488, 1520, 1524, 1528, 1530, 1532, 1533, 1534, 1535, 1984, 2000, 2016
OFFSET
1,2
COMMENTS
If n is a term, then 2*n is also a term, and vice versa.
PROG
(PARI)
A048720(b, c) = fromdigits(Vec(Pol(binary(b))*Pol(binary(c)))%2, 2);
is_A391738(k) = (25*k == A048720(41, k));
CROSSREFS
Cf. A048720.
Row 25 of A115872 (without the initial 0).
Subsequence of A391858.
Cf. also A391737, A391739.
Sequence in context: A078855 A053430 A040930 * A115809 A303698 A164012
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, Dec 21 2025
STATUS
approved