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A331206
Numbers k such that A053985(k) divides k.
0
1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 17, 20, 21, 24, 30, 32, 34, 40, 42, 48, 51, 60, 63, 64, 65, 68, 69, 80, 81, 84, 85, 96, 102, 120, 126, 128, 130, 136, 138, 160, 162, 168, 170, 192, 195, 204, 207, 240, 243, 252, 255, 256, 257, 260, 261, 272, 273, 276, 277
OFFSET
1,2
COMMENTS
It appears that A053985(a(n)) / a(n) is always either 1, -1, 3 or -3.
This sequence seems to contain A329000.
EXAMPLE
15 is written 1111 base 2 and (-2)^3 + (-2)^2 + (-2)^1 +(-2)^0 = -8 + 4 - 2 + 1 = -5, 15 is divisible by -5.
PROG
(PARI) is(k) = k%fromdigits(binary(k), -2) == 0; \\ Jinyuan Wang, Jan 15 2020
CROSSREFS
Sequence in context: A182418 A204580 A347831 * A295298 A003401 A281624
KEYWORD
nonn,base
AUTHOR
Alon Ran, Jan 12 2020
STATUS
approved