A157676 -id:A157676 - cp's OEIS frontend

A229221 Numbers k such that k - (product of digits of k) is prime.

21, 23, 27, 29, 41, 43, 47, 49, 81, 83, 87, 89, 101, 103, 107, 109, 127, 141, 143, 149, 181, 187, 223, 227, 229, 241, 247, 251, 253, 263, 271, 277, 293, 299, 307, 343, 347, 349, 367, 383, 389, 401, 409, 413, 417, 419, 431, 433, 437, 439, 451, 457, 471, 473, 477, 479, 481, 487, 503, 509, 527, 529, 541

Offset: 1

Derek Orr, Sep 16 2013

Cf. A157676.

fQ[n_] := Module[{q = n - Times @@ IntegerDigits[n]}, q > 0 && PrimeQ[q]]; Select[Range[500], fQ] (* T. D. Noe, Sep 17 2013 *)

for(n=1,10^3,d=digits(n);p=prod(i=1,#d,d[i]);if(isprime(n-p),print1(n,", "))) \\ Derek Orr, Apr 10 2015

from sympy import isprime
def DP(n):
    p = 1
    for i in str(n):
        p *= int(i)
    return p
{print(n,end=', ') for n in range(10**3) if isprime(n-DP(n))}
## Simplified by Derek Orr, Apr 10 2015

[x for x in range(1000) if (x-prod(Integer(x).digits(base=10))) in Primes()] # Tom Edgar, Sep 18 2013

More terms from Derek Orr, Apr 10 2015

A227948 Zeroless numbers n such that n + (product of digits of n) and n - (product of digits of n) are prime.

Original entry on oeis.org

21, 23, 27, 29, 81, 83, 253, 293, 299, 343, 347, 349, 431, 437, 439, 471, 473, 477, 529, 623, 653, 659, 677, 743, 893, 1123, 1219, 1253, 1257, 1297, 1423, 1489, 1521, 1523, 1529, 1587, 1589, 1657, 1763, 1853, 1867, 1927, 2151, 2167, 2239, 2277, 2279, 2321, 2327, 2329, 2377, 2413, 2443, 2459, 2467, 2497, 2543, 2569

Offset: 1

Derek Orr, Oct 04 2013

Intersection of A157676 and A229221 (without the primes containing zero digits).

			29 - 2*9 = 11 (prime) and 29 + 2*9 = 47 (prime) so 29 is a member of this sequence.
743 - 7*4*3 = 659 (prime) and 743 + 7*4*3 = 827 (prime) so 743 is a member of this sequence.

Cf. A157676, A229221, A007954, A052382.

for(n=1,5000,d=digits(n);p=prod(i=1,#d,d[i]);if(p&&isprime(n+p)&&isprime(n-p),print1(n,", "))) \\ Derek Orr, Apr 05 2015

from sympy import isprime
def DP(n):
  p = 1
  for i in str(n):
    p *= int(i)
  return p
{print(n,end=', ') for n in range(5000) if DP(n) and isprime(n+DP(n)) and isprime(n-DP(n))}
## Simplified by Derek Orr, Apr 05 2015

More terms from Derek Orr, Apr 05 2015

cp's OEIS Frontend

A229221 Numbers k such that k - (product of digits of k) is prime.

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