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%I #23 Sep 08 2022 08:45:00
%S 2,3,5,7,1,3,7,9,6,18,3,21,4,12,28,15,45,6,42,7,21,63,24,72,63,0,0,0,
%T 0,3,14,3,21,27,36,5,35,18,42,21,63,8,9,27,63,81,2,12,28,36,18,54,8,
%U 10,70,36,108,14,98,16,48,54,0,3,9,21,9,63,84,108,45,135,126,63,189,72,216,189
%N Product of digits of n-th prime.
%H Vincenzo Librandi, <a href="/A053666/b053666.txt">Table of n, a(n) for n = 1..1000</a>
%e a(25) = 63 because the 25th prime is 97, and 9 * 7 = 63.
%e a(26) = 0 because the 26th prime is 101, and 1 * 0 * 1 = 0.
%p a:= n-> mul(i, i=convert(ithprime(n), base, 10)):
%p seq(a(n), n=1..78); # _Alois P. Heinz_, Mar 11 2022
%t Table[Times@@IntegerDigits[Prime[n]], {n, 80}] (* _Alonso del Arte_, Feb 28 2014 *)
%o (PARI) a(n) = {d = digits(prime(n), 10); return (prod(i=1, #d, d[i]));} \\ _Michel Marcus_, Jun 12 2013
%o (Magma) [&*Intseq(NthPrime(n)): n in [1..80]]; // _Vincenzo Librandi_, Sep 15 2014
%o (Python)
%o from math import prod
%o from sympy import sieve
%o def pod(n): return prod(map(int, str(n)))
%o def a(n): return pod(sieve[n])
%o print([a(n) for n in range(1, 79)]) # _Michael S. Branicky_, Mar 11 2022
%Y Cf. A007954.
%K nonn,base,easy
%O 1,1
%A _Enoch Haga_, Feb 16 2000
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