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A228139
Primes such that the product of their digits subtracted from the prime number is another prime.
2
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
OFFSET
1,1
LINKS
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
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