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Smallest n-th power whose digit reversal is a prime.
0

%I #12 Feb 17 2021 02:12:32

%S 2,16,125,16,32,16777216,128,16777216,35184372088832,1024,

%T 34271896307633,16777216,1490116119384765625,182059119829942534144,

%U 35184372088832,3876269050118516845397872321,131072,14551915228366851806640625,1134787999706880954999833295916475119,3584859224085422343574104404449462890625

%N Smallest n-th power whose digit reversal is a prime.

%o (Python)

%o from sympy import isprime

%o def a(n):

%o k = 1

%o while not isprime(int(str(k**n)[::-1])): k += 1

%o return k**n

%o print([a(n) for n in range(1, 21)]) # _Michael S. Branicky_, Feb 16 2021

%K nonn,base

%O 1,1

%A _Amarnath Murthy_, Apr 21 2002

%E More terms from _Jason Earls_, Jun 03 2002