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A053666
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Product of digits of n-th prime.
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28
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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, 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, 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
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(25) = 63 because the 25th prime is 97, and 9 * 7 = 63.
a(26) = 0 because the 26th prime is 101, and 1 * 0 * 1 = 0.
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MAPLE
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a:= n-> mul(i, i=convert(ithprime(n), base, 10)):
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MATHEMATICA
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Table[Times@@IntegerDigits[Prime[n]], {n, 80}] (* Alonso del Arte, Feb 28 2014 *)
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PROG
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(PARI) a(n) = {d = digits(prime(n), 10); return (prod(i=1, #d, d[i])); } \\ Michel Marcus, Jun 12 2013
(Python)
from math import prod
from sympy import sieve
def pod(n): return prod(map(int, str(n)))
def a(n): return pod(sieve[n])
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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