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The base in which A256360(n) is multi-narcissistic.
2

%I #24 Sep 21 2015 20:37:54

%S 3,3,7,5,5,8,7,21,7,4,31,17,9,4,8,23,4,17,11,4,57,30,11,18,73,4,27,8,

%T 22,13,6,91,47,33,15,18,5,111,9,15,7,27,68,7,17,157,80,55,28,19,43,6,

%U 183,32,21,18,211,107,73,21,4,14,241,64,37,53,23,5,273,46

%N The base in which A256360(n) is multi-narcissistic.

%H Tim Johannes Ohrtmann, <a href="/A258273/b258273.txt">Table of n, a(n) for n = 1..49477</a>

%e a(1) = 3 because this is the base in which A256360(1) is a multiple-digit narcissistic number: 5 is 12 in base 3 and 1^2+2^2 = 5.

%o (PARI) for(n=3, 1000000, k=0; for(z=2, n, y=n; j=0; L=List(); until(y==0, x=y%z; j++; listinsert(L, x, j); while(!((y%z)==0), y--); y=y/z); t=0; for(p=1, j, t+=L[p]^j); if(n==t, k++; a=z)); if(k==1, print1(a, ", ")))

%Y Cf. A256360.

%K nonn,base

%O 1,1

%A _Tim Johannes Ohrtmann_, Jun 25 2015