A303492 Numbers m such that m divides A302205(m).
1, 2, 3, 4, 6, 8, 9, 10, 12, 16, 18, 20, 24, 27, 30, 32, 36, 40, 48, 60, 64, 72, 80, 90, 96, 100, 112, 120, 128, 130, 144, 160, 180, 184, 190, 192, 200, 224, 240, 249, 256, 260, 270, 279, 288, 300, 306, 320, 360, 384, 400, 401, 408, 412, 480, 512, 520, 528, 558, 576, 600, 612, 640
Offset: 1
Examples
With k = 18, b = 10010, and x = concat(16,0,0,2,0) = 160020, we find that 160020 / 18 = 8890, so 18 is in this sequence.
Crossrefs
Cf. A302205.
Programs
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PARI
isok(n) = {my(b = binary(n)); s = ""; forstep (k=#b, 1, -1, s = concat(s, Str(b[#b-k+1]*2^(k-1)))); eval(s) % n == 0;} \\ Michel Marcus, Apr 26 2018 -
Python
k = 1000 seq = [] for i in range(1,k+1): b = bin(i)[2:] c = len(b) x = "" for j in range(c): x += str(int(pow(2,c-j-1)) * int(b[j])) y = float(int(x))/float(i) if y.is_integer(): seq.append(i) print(seq)
Extensions
Edited by N. J. A. Sloane, Apr 26 2018