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Numbers that are multiple-digit narcissistic numbers in exactly five bases.
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%I #16 Feb 17 2021 23:26:37

%S 274625,465125,528125,710645,912925,983125

%N Numbers that are multiple-digit narcissistic numbers in exactly five bases.

%H W. Schneider, <a href="http://web.archive.org/web/20050213060737/http://www.wschnei.de/digit-related-numbers/pdi.html">Perfect Digital Invariants: Pluperfect Digital Invariants(PPDIs)</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/NarcissisticNumber.html">Narcissistic Number</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Narcissistic_number">Narcissistic number</a>

%e a(1) = 274625 because this is the first number that is a multiple-digit narcissistic number in exactly five bases (528, 603, 1318, 1958 and 4217).

%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++)); if(k==5, print1(n, ", ")))

%Y Cf. A005188.

%Y Cf. A256359 (every number of bases).

%Y Cf. A256360, A256361, A256362, A256363, A256365 (1 to 4 and 6 bases).

%Y Cf. A256459 (first occurrences).

%K nonn,base,more

%O 1,1

%A _Tim Johannes Ohrtmann_, Mar 30 2015