A058997 - OEIS

A058997

Least power k greater than 1 for which n^k reversed is a prime, or 0 if impossible.

0, 4, 0, 2, 3, 0, 12, 8, 0, 0, 0, 0, 379, 2, 0, 6, 11, 0, 2, 0, 0, 0, 8, 0, 13, 47, 0, 2, 7, 0, 4, 2, 0

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..33.

MATHEMATICA

Do[ If[ Mod[ n, 3 ] != 0 && Mod[ n, 10 ] != 0 && Mod[ n, 11 ] != 0, k = 2; While[ !PrimeQ[ ToExpression[ StringReverse[ ToString[ n^k ] ] ] ], k++ ]; Print[ k ], Print[ 0 ] ], {n, 2, 33} ]

CROSSREFS

Sequence in context: A109157 A226955 A123314 * A261164 A323982 A279415

Adjacent sequences: A058994 A058995 A058996 * A058998 A058999 A059000

KEYWORD

base,nonn

AUTHOR

Robert G. Wilson v, Jan 17 2001

STATUS

approved