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%I #7 Jan 13 2025 17:34:42
%S 0,0,0,0,0,0,0,0,0,4,0,3,4,6,9,11,12,15,16,7,3,0,2,4,6,9,11,13,14,8,4,
%T 2,0,2,4,7,8,10,12,10,6,4,2,0,2,4,6,8,9,12,9,6,4,2,0,2,5,7,7,14,11,9,
%U 7,4,2,0,2,4,5,15,12,11,8,6,5,2,0,2,2,18,15,13,10,8,7,4,2,0,1,20,16,14
%N Number of primes between n and R(n) where R(n) (A004086) is the digit reversal of n.
%H John Tyler Rascoe, <a href="/A060568/b060568.txt">Table of n, a(n) for n = 1..10000</a>
%e a(10) = 4, as there are four primes between 10 and 1.
%o (Python)
%o from sympy import primerange
%o def A060568(n):
%o x = (n, int(str(n)[::-1],10))
%o return len([i for i in primerange(min(x)+1,max(x))]) # _John Tyler Rascoe_, Jan 13 2025
%Y Cf. A000720, A074813.
%K nonn,base,easy,changed
%O 1,10
%A _Amarnath Murthy_, Apr 27 2001
%E More terms from Larry Reeves (larryr(AT)acm.org), May 10 2001