A066027 Numbers k such that the sum of digits of k minus the product of digits of k is prime.

20, 30, 50, 70, 101, 102, 104, 106, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 131, 140, 141, 151, 160, 161, 171, 181, 191, 200, 201, 203, 205, 209, 210, 211, 230, 250, 290, 300, 302, 304, 308, 311, 320, 340, 380, 401, 403, 407, 409, 410

Offset

1,1

Links

Harry J. Smith, Table of n, a(n) for n = 1..1000

Example

a(11)=112 because 1 + 1 + 2 = 4, 2*1*1 = 2, and 4 - 2 = 2, which is prime. [corrected by Harry J. Smith, Nov 07 2009]

Prog

(PARI) isok(k) = {my(d=digits(k)); isprime(vecsum(d) - vecprod(d))} \\ Harry J. Smith, Nov 07 2009

Crossrefs

Cf. A066024, A038369.

Sequence in context: A120145 A104048 A078499 * A256227 A142342 A008444

Adjacent sequences: A066024 A066025 A066026 * A066028 A066029 A066030

Keyword

easy,nonn,base

Author

Enoch Haga, Dec 11 2001

Status

approved