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A228139

Primes such that the product of their digits subtracted from the prime number is another prime.

23, 29, 41, 43, 47, 83, 89, 127, 149, 181, 223, 227, 229, 241, 251, 263, 271, 277, 293, 347, 349, 367, 383, 389, 419, 431, 433, 439, 457, 479, 487, 541, 587, 631, 641, 643, 647, 653, 659, 673, 677, 743, 761, 853, 857, 859, 863, 883, 887, 1123, 1229, 1279, 1297, 1423, 1459, 1489, 1523

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OFFSET

1,1

LINKS

Paolo P. Lava, Table of n, a(n) for n = 1..1000

EXAMPLE

23 is a member since 23-(2*3)=17. 29 is a member since 29-(2*9)=11.

MATHEMATICA

pdsQ[n_]:=Module[{pr=Times@@IntegerDigits[n]}, pr!=0&&PrimeQ[n-pr]]; Select[Prime[Range[300]], pdsQ] (* Harvey P. Dale, Jul 29 2017 *)

PROG

(PARI) dprod(n)=my(v=digits(n)); prod(i=1, #v, v[i])

is(n)=my(d=dprod(n)); d>0 && isprime(n) && isprime(n-d) \\ Charles R Greathouse IV, Aug 12 2013

CROSSREFS

Subsequence of A038618.

Sequence in context: A144226 A173709 A225319 * A094383 A166565 A050207

Adjacent sequences: A228136 A228137 A228138 * A228140 A228141 A228142

KEYWORD

nonn,base

AUTHOR

Will Gosnell, Aug 12 2013

EXTENSIONS

a(3), a(10), a(15)-a(57) from Charles R Greathouse IV, Aug 12 2013

STATUS

approved