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 A066521 Primes p(k) such that the product of digits of p(k) equals the product of digits of k. 1
 17, 181, 443, 491, 1163, 2131, 2143, 2153, 2621, 4253, 4621, 7691, 11483, 11593, 11813, 23819, 26951, 27179, 32261, 32443, 33811, 35171, 35227, 37643, 41543, 42433, 42443, 44623, 44917, 45971, 51473, 54517, 58193, 61223, 63131, 64591 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Numbers with product of digits=0, like prime(80) = 409, are not included. - Harry J. Smith, Feb 20 2010 LINKS Harry J. Smith, Table of n, a(n) for n = 1..1000 EXAMPLE 181 is the 42nd prime and the product of digits of both is 8. PROG (PARI) ProdD(x)= { local(p=1); while (x>9 && p>0, p*=x%10; x\=10); return(p*x) } { n=0; for (m=1, 10^10, p=prime(m); d=ProdD(m); if (ProdD(p) == d && d, write("b066521.txt", n++, " ", p); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 20 2010 CROSSREFS Cf. A007954, A033548. Sequence in context: A125405 A130651 A142214 * A055904 A116964 A167578 Adjacent sequences:  A066518 A066519 A066520 * A066522 A066523 A066524 KEYWORD base,less,nonn AUTHOR Jason Earls, Jan 05 2002 STATUS approved

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Last modified September 20 22:20 EDT 2019. Contains 327252 sequences. (Running on oeis4.)