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A030091 Primes such that p and p^2 have same set of digits. 2
94583, 100469, 102953, 107251, 110923, 184903, 279863, 285101, 406951, 459521, 493621, 499423, 504821, 684581, 752681, 758141, 758941, 786431, 836291, 843701, 928637, 976513, 980261, 1008947, 1009859, 1024399, 1029647 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

FORMULA

Equals A000040 INTERSECTION A029793. - Jonathan Vos Post, Jul 06 2008

MATHEMATICA

Select[Prime[Range[82000]], Union[IntegerDigits[#]]== Union[ IntegerDigits [#^2]]&] (* Harvey P. Dale, Aug 12 2011 *)

PROG

(PARI) isA030091(n)=isprime(n)&&Set(Vec(Str(n)))==Set(Vec(Str(n^2))) \\ Charles R Greathouse IV, Jun 28 2011

(Haskell)

import Data.List (nub, sort)

import Data.Function (on)

a030091 n = a030091_list !! (n-1)

a030091_list =

   filter (\x -> ((==) `on` (nub . sort . show)) x (x^2)) a000040_list

-- Reinhard Zumkeller, Aug 11 2011

CROSSREFS

Cf. A000040, A029793.

Sequence in context: A348021 A248067 A252323 * A128376 A216122 A206411

Adjacent sequences:  A030088 A030089 A030090 * A030092 A030093 A030094

KEYWORD

nonn,base,nice

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified May 22 10:56 EDT 2022. Contains 353949 sequences. (Running on oeis4.)