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

Author

Rémy Sigrist, Oct 17 2019

Keywords

• nonn
• base
• look

Examples

			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.
		

Links

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

Crossrefs

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

Cf. A062383.

Programs

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]);

PARI

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

Formula

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

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