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Smallest perfect power b^e such that b^e+n is also a perfect power, or 0 if no such perfect power exists.
4

%I #7 Aug 09 2023 07:06:21

%S 8,25,1,4,4,0,1,1,16,2187,16,4,36,0,1,9,8,9,8,16,4,27,4,1,100,1,9,4,

%T 196,6859,1,4,16,0,1,64,27,1331,25,9,8,0,441,81,4,243,81,1,32,0,49,

%U 144,676,27,9,8,64,0,841,4,64,0,1,36,16,0,1089

%N Smallest perfect power b^e such that b^e+n is also a perfect power, or 0 if no such perfect power exists.

%C a(A074981(n)) = 0.

%F a(n) = A074954(n)-n, if A074954(n)>0; a(n)=0, if A074954(n)=0.

%Y Cf. A074954, A001597, A076444, A023056.

%K nonn

%O 1,1

%A _Max Alekseyev_, Feb 22 2005

%E Offset corrected by _Mohammed Yaseen_, Aug 09 2023