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 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 (list; graph; refs; listen; history; text; internal format)
 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. A029447-A029470, A029471-A029494, A029495-A029518, A029519-A029542, A061931-A061954, A061955-A061978. Sequence in context: A111794 A030290 A099088 * A212317 A161751 A245820 Adjacent sequences:  A029444 A029445 A029446 * A029448 A029449 A029450 KEYWORD nonn,base AUTHOR 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

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Last modified December 12 17:21 EST 2018. Contains 318080 sequences. (Running on oeis4.)