A308983 Numbers n such that A308803(2n+1) = (2*10^n-1)(5*10^n+1).

4, 15, 18, 20, 23, 29, 33, 34, 35, 36, 38, 39, 43, 48, 49, 50, 54, 56, 60, 62, 63, 66, 68, 69, 74, 75, 77, 78, 81, 83, 84, 86, 88, 89

Offset: 1

Author

Chai Wah Wu, Sep 30 2019

Keywords

• nonn
• base
• more

Comments

A308803(2n+1) >= (2*10^n-1)(5*10^n+1) for all n. This sequence lists the values of n where this lower bound is attained.

Crossrefs

Cf. A308803

Extensions

a(14)-a(34) from Chai Wah Wu, Oct 03 2019