A054750 Smallest prime number whose digits sum to n-th prime.

2, 3, 5, 7, 29, 67, 89, 199, 599, 2999, 4999, 29989, 59999, 79999, 389999, 989999, 6999899, 8989999, 59899999, 89999999, 289999999, 799999999, 3999998999, 19999997999, 79999999999, 399999998999, 599999899999, 999998999999

Offset

1,1

Comments

a(n) >= A051885(A000040(n)). Indices n for which the equality holds are listed in A055019.

a(n) >= A046864(n). - Michel Marcus, Nov 01 2015

Links

Table of n, a(n) for n=1..28.

Chris Caldwell and G. L. Honaker, Jr., Prime curio for 8999

Example

E.g. a(7)=89 because 8+9=17 and 17 is the 7th prime.

Prog

(PARI) a(n) = {my(k=2); my(p=prime(n)); while((sumdigits(k) != prime(n)), k=nextprime(k+1)); k; } \\ Michel Marcus, Nov 01 2015

Crossrefs

Cf. A000040, A067180, A046704, A046704, A046864, A068951, A007605.

Sequence in context: A046864 A090712 A082257 * A048404 A052013 A269022

Adjacent sequences: A054747 A054748 A054749 * A054751 A054752 A054753

Keyword

base,nonn

Author

G. L. Honaker, Jr., Apr 24 2000

Extensions

More terms from Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), May 31 2000

Edited and extended by Robert G. Wilson v, Feb 26 2002

Status

approved