A326302 a(n) = lcm(n, r(n)) where r(n) = A030101(n) corresponds to the binary reversal of n.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 143, 12, 143, 14, 15, 16, 17, 18, 475, 20, 21, 286, 667, 24, 475, 286, 27, 28, 667, 30, 31, 32, 33, 34, 245, 36, 1517, 950, 741, 40, 1517, 42, 2279, 572, 45, 1334, 2867, 48, 245, 950, 51, 572, 2279, 54, 3245, 56, 741, 1334, 3245

Offset

0,3

Links

Rémy Sigrist, Table of n, a(n) for n = 0..8192

Formula

a(n) >= n with equality iff n belongs to A057890.

a(n) < A062383(n)*n. - Robert Israel, Oct 17 2019

Example

For n = 35:
- the binary reversal of 35 ("100011" in binary) is 49 ("110001" in binary),
- hence a(35) = lcm(35, 49) = lcm(5*7, 7^2) = 5*7^2 = 245.

Maple

f:= proc(n) local L, j;
  L:= convert(n, base, 2);
  ilcm(n, add(2^(j-1)*L[-j], j=1..nops(L)))
end proc:
map(f, [$0..100]);

Prog

(PARI) a(n, base=2) = lcm(n, fromdigits(Vecrev(digits(n, base)), base))

Crossrefs

Cf. A030101, A057890 (fixed points), A161825 (GCD variant), A068634 (decimal variant).

Cf. A062383.

Sequence in context: A061378 A004872 A078295 * A004883 A004894 A004905

Adjacent sequences: A326299 A326300 A326301 * A326303 A326304 A326305

Keyword

nonn,base,look

Author

Rémy Sigrist, Oct 17 2019

Status

approved