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%I #22 Dec 22 2021 09:05:14
%S 0,0,1,0,1,0,1,2,0,0,3,4,8,0,6,11,3,0,3,6,1,1,4,3,0,2,5,6,15,15,17,16,
%T 12,12,4,10,8,5,8,18,11,23,5,13,9,10,8,6,27,9,4,6,14,4,24,3,14,6,4,33,
%U 7,14,11,12,6,86,26,53,13,79,27,51,81,61,26,39,25,54,17,25
%N Number of ways to rearrange digits of prime(n)*prime(n+1) to form a prime.
%C Leading zeros are not allowed in the rearranged number.
%H Michael S. Branicky, <a href="/A053653/b053653.txt">Table of n, a(n) for n = 1..10000</a>
%e a(8) = 2 because 19*23 = 437 and 2 primes, 347 and 743, can be formed from the digits of 437.
%o (Python)
%o from sympy import isprime, prime
%o from sympy.utilities.iterables import multiset_permutations as mp
%o def c(s):
%o return sum(1 for t in mp(s) if t[0]!='0' and isprime(int("".join(t))))
%o def a(n): return c(str(prime(n)*prime(n+1)))
%o print([a(n) for n in range(1, 72)]) # _Michael S. Branicky_, Dec 22 2021
%Y Cf. A053652, A053736.
%K easy,nonn,look,base
%O 1,8
%A _Enoch Haga_, Feb 18 2000
%E Edited by _Jens Kruse Andersen_, Dec 01 2006
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