A004087 Primes written backwards.

2, 3, 5, 7, 11, 31, 71, 91, 32, 92, 13, 73, 14, 34, 74, 35, 95, 16, 76, 17, 37, 97, 38, 98, 79, 101, 301, 701, 901, 311, 721, 131, 731, 931, 941, 151, 751, 361, 761, 371, 971, 181, 191, 391, 791, 991, 112, 322, 722, 922, 332, 932, 142, 152, 752, 362, 962, 172

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• base
• look

Links

• R. Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000040.

Programs

Haskell

a004087 n = a004087_list !! (n-1)
a004087_list = map a004086 a000040_list
-- Reinhard Zumkeller, Oct 14 2011

Magma

[Seqint(Reverse(Intseq(NthPrime(n)))): n in [1..60]]; // Vincenzo Librandi, Jan 21 2016

Mathematica

FromDigits[Reverse[IntegerDigits[#]]]&/@Prime[Range[100]] (* Vincenzo Librandi, Jul 05 2015 *)

Python

from sympy import primerange
print([int(str(p)[::-1]) for p in primerange(2, 272)]) # Michael S. Branicky, Jun 24 2022

Formula

a(n) = A004086(A000040(n)) = A000040(n) - A068396(n). - N. J. A. Sloane, Jun 29 2008

a(n) = A188649(A000040(n)). - Reinhard Zumkeller, Apr 11 2011

a(n) = A071786(A000040(n)). - Reinhard Zumkeller, Oct 14 2011

Extensions

More terms from Eric M. Schmidt, Apr 04 2014