A066027 Sum of digits of n minus product of digits of n 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) ProdD(x)= { local(p=1); while (x>9 && p>0, p*=x%10; x\=10); return(p*x) } SumD(x)= { local(s=0); while (x>9, s+=x%10; x\=10); return(s + x) } { n=0; for (m=1, 10^9, if (isprime(SumD(m) - ProdD(m)), write("b066027.txt", n++, " ", m); if (n==1000, return)) ) } \\ 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