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Binary representation of n interpreted in base p, where p is the smallest prime factor of n: p = A020639(n).
10

%I #11 Aug 02 2020 04:12:15

%S 1,2,4,4,26,6,57,8,28,10,1343,12,2367,14,40,16,83522,18,130341,20,91,

%T 22,280394,24,751,26,112,28,732512,30,954305,32,244,34,3131,36,

%U 69345327,38,256,40,115925123,42,147087994,44,280,46,229451087,48

%N Binary representation of n interpreted in base p, where p is the smallest prime factor of n: p = A020639(n).

%C n>1: a(n) = n iff n is even.

%C a(n) = A005836(n) iff n=6k-3, k>0 (see A016945).

%C The following sequences all appear to have the same parity: A003071, A029886, A061297, A092524, A093431, A102393, A104258, A122248, A128975. - _Jeremy Gardiner_, Dec 28 2008

%e n = 35 = 7*5 = '100011': 2^5 + 2^1 + 2^0 -> a(35) = 5^5 + 5^1 + 5^0 = 3125+5+1 = 3131.

%t a[n_] := If[EvenQ[n], n, FromDigits[IntegerDigits[n, 2], FactorInteger[n][[1, 1]]]]; Array[a, 50] (* _Amiram Eldar_, Aug 02 2020 *)

%Y Cf. A005836, A007088, A020639.

%Y Cf. A003071, A029886, A061297, A092524, A093431, A102393, A104258, A122248, A128975.

%K nonn,base

%O 1,2

%A _Reinhard Zumkeller_, Apr 07 2004