

A029447


Numbers n that divide the (right) concatenation of all numbers <= n written in base 2 (most significant digit on left).


142



1, 2, 3, 4, 5, 7, 8, 16, 26, 32, 38, 40, 46, 64, 96, 128, 138, 192, 228, 256, 512, 640, 1024, 2048, 4096, 4192, 4766, 4790, 5142, 5952, 6144, 6866, 8122, 8192, 8448, 10240, 11283, 11392, 12288, 14780, 15360, 15744, 16384, 17408, 20841, 20866, 32768, 58496, 59104
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OFFSET

1,2


COMMENTS

All powers of 2 are in the sequence.  Chai Wah Wu, Nov 10 2014
Numbers n that divide A047778(n).  Michel Marcus, Nov 11 2014


LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..54


EXAMPLE

3 is in the sequence because the concatenation is 1 10 11, binary expansion of 27, that is divisible by 3.


MATHEMATICA

Select[Range[2^13], Mod[FromDigits[Flatten[IntegerDigits[#, 2] & /@ Range@ #], 2], #] == 0 &] (* Michael De Vlieger, Aug 29 2015 *)


PROG

(PARI) lista(nn) = {vs = []; for (n=1, nn, vs = concat(vs, binary(n)); val = subst(Pol(vs), x, 2); if (val % n == 0, print1(n, ", ")); ); } \\ Michel Marcus, Nov 11 2014


CROSSREFS

Cf. A029447A029470, A029471A029494, A029495A029518, A029519A029542, A061931A061954, A061955A061978.
Sequence in context: A111794 A030290 A099088 * A212317 A161751 A245820
Adjacent sequences: A029444 A029445 A029446 * A029448 A029449 A029450


KEYWORD

nonn,base


AUTHOR

Olivier Gérard


EXTENSIONS

More terms from Scott Lindhurst (ScottL(AT)alumni.princeton.edu)
More terms from David W. Wilson
a(47)a(49) from Chai Wah Wu, Nov 10 2014


STATUS

approved



