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A115711 Squares whose digit reversal is a semiprime (A001358). 2
4, 9, 49, 64, 121, 169, 289, 400, 625, 900, 961, 1156, 1225, 1849, 2401, 3136, 3364, 3481, 3721, 4900, 5041, 5329, 6400, 6889, 7396, 9604, 10201, 10816, 11449, 11881, 12100, 12544, 12769, 13225, 13456, 13924, 15376, 15625, 16129, 16384, 16900 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..41.

EXAMPLE

64=8^2 and 46=2*23 is semiprime.

MATHEMATICA

Select[Range[150]^2, PrimeOmega[FromDigits[Reverse[ IntegerDigits[ #]]]]==2&] (* Harvey P. Dale, Sep 20 2011 *)

CROSSREFS

Cf. A001358, A115710.

Sequence in context: A225885 A247267 A115687 * A029791 A053961 A055812

Adjacent sequences:  A115708 A115709 A115710 * A115712 A115713 A115714

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, Jan 31 2006

STATUS

approved

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Last modified March 30 16:16 EDT 2020. Contains 333127 sequences. (Running on oeis4.)