A069664 Largest n-digit prime with minimum digit sum.

2, 11, 101, 3001, 21001, 102001, 2100001, 30000001, 200001001, 2010000001, 30000000001, 110000000101, 2000001000001, 20000000100001, 200000010000001, 1100010000000001, 20000001000000001, 110000000000000101, 2000000000000100001, 20000000100000000001

Offset: 1

Author

Amarnath Murthy, Apr 05 2002

Keywords

• nonn
• base

Links

• Joel B. Lewis and T. D. Noe, Table of n, a(n) for n = 1..100

Crossrefs

Cf. A007953, A069661, A069662, A069663.

Programs

Mathematica

Table[ Max[ Flatten[Table[ If[PrimeQ[10^n + 1], 10^n + 1, If[PrimeQ[10^n + 10^i + 10^j + 1], 10^n + 10^i + 10^j + 1, 0]], {i, 0, n}, {j, 0, i}]]], {n, 0, 50}] (* Program works so long as there exists an n-digit prime with digit sum 4 or less. *)

Extensions

a(7)-a(12) from Tom Mueller, Apr 28 2004

a(13) and onwards added by Joel B. Lewis, Jan 07 2008