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A079154
Numbers n such that reverse(A004154(n)) - 1 is prime.
0
3, 4, 12, 30, 33, 1406
OFFSET
1,1
COMMENTS
The values corresponding to a(1)-a(6) have been certified prime with Primo. a(7) > 15000. - Giovanni Resta, Feb 20 2013
MATHEMATICA
f[n_] := n!/10^Sum[Floor[n/5^k], {k, 1, Log[10, n] + 1}]; Do[ If[ PrimeQ[ FromDigits[ Reverse[ IntegerDigits[ f[n]]]] - 1], Print[n]], {n, 1, 800}]
CROSSREFS
Sequence in context: A287594 A296271 A000208 * A101716 A360992 A217477
KEYWORD
base,more,nonn
AUTHOR
EXTENSIONS
a(6) from Giovanni Resta, Feb 20 2013
STATUS
approved