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Primes written backwards.
34

%I #37 Jun 24 2022 20:14:26

%S 2,3,5,7,11,31,71,91,32,92,13,73,14,34,74,35,95,16,76,17,37,97,38,98,

%T 79,101,301,701,901,311,721,131,731,931,941,151,751,361,761,371,971,

%U 181,191,391,791,991,112,322,722,922,332,932,142,152,752,362,962,172

%N Primes written backwards.

%H R. Zumkeller, <a href="/A004087/b004087.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A004086(A000040(n)) = A000040(n) - A068396(n). - _N. J. A. Sloane_, Jun 29 2008

%F a(n) = A188649(A000040(n)). - _Reinhard Zumkeller_, Apr 11 2011

%F a(n) = A071786(A000040(n)). - _Reinhard Zumkeller_, Oct 14 2011

%t FromDigits[Reverse[IntegerDigits[#]]]&/@Prime[Range[100]] (* _Vincenzo Librandi_, Jul 05 2015 *)

%o (Haskell)

%o a004087 n = a004087_list !! (n-1)

%o a004087_list = map a004086 a000040_list

%o -- _Reinhard Zumkeller_, Oct 14 2011

%o (Magma) [Seqint(Reverse(Intseq(NthPrime(n)))): n in [1..60]]; // _Vincenzo Librandi_, Jan 21 2016

%o (Python)

%o from sympy import primerange

%o print([int(str(p)[::-1]) for p in primerange(2, 272)]) # _Michael S. Branicky_, Jun 24 2022

%Y Cf. A000040.

%K nonn,base,look

%O 1,1

%A _N. J. A. Sloane_

%E More terms from _Eric M. Schmidt_, Apr 04 2014