A047791 Numbers n such that n plus digit sum of n (A007953) equals a prime.

1, 10, 11, 13, 14, 16, 19, 32, 34, 35, 37, 52, 53, 56, 58, 59, 71, 73, 76, 91, 92, 94, 95, 97, 100, 101, 103, 104, 106, 122, 124, 127, 128, 142, 143, 146, 149, 160, 163, 166, 167, 181, 182, 184, 185, 215, 217, 218, 232, 233, 238, 250, 253, 256, 257, 271, 272

Offset: 1

Author

G. L. Honaker, Jr.

Keywords

• base
• easy
• nonn

Examples

			Digit sum of 13 = 1 + 3 = 4 -> 13 + 4 = 17 is prime.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
• Index entries for Colombian or self numbers and related sequences

Crossrefs

Cf. A006378, A107740.

Cf. A007953, A062028, A010051, A107743.

Programs

Haskell

a047791 n = a047791_list !! (n-1)
a047791_list = filter ((== 1) . a010051' . a062028) [1..]
-- Reinhard Zumkeller, Sep 27 2014

Mathematica

Select[Range[272],PrimeQ[#+Total[IntegerDigits[#]]]&] (* Jayanta Basu, May 03 2013 *)

PARI

select( is(n)=isprime(n+sumdigits(n)), [1..300]) \\ M. F. Hasler, Nov 08 2018

Formula

Complement of A107743.

A062028^(-1)(A000040). - M. F. Hasler, Nov 08 2018

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Nov 16 2000