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Numbers m such that m divides A302205(m).
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%I #17 Sep 25 2023 14:59:50

%S 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,

%T 100,112,120,128,130,144,160,180,184,190,192,200,224,240,249,256,260,

%U 270,279,288,300,306,320,360,384,400,401,408,412,480,512,520,528,558,576,600,612,640

%N Numbers m such that m divides A302205(m).

%e 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.

%o (Python)

%o k = 1000

%o seq = []

%o for i in range(1,k+1):

%o b = bin(i)[2:]

%o c = len(b)

%o x = ""

%o for j in range(c):

%o x += str(int(pow(2,c-j-1)) * int(b[j]))

%o y = float(int(x))/float(i)

%o if y.is_integer():

%o seq.append(i)

%o print(seq)

%o (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

%Y Cf. A302205.

%K nonn,base

%O 1,2

%A _J. Stauduhar_, Apr 24 2018

%E Edited by _N. J. A. Sloane_, Apr 26 2018