61

This number is a prime.

Single Curio View: (Seek other curios for this number)

The 61 1st-move pairs in chess yielding the minimum 19 2nd-move options for White are the symmetrical double advances of King-Bishop Pawns and all 20 responses with either that pawn's or either Rook Pawn's single advance. [Merickel]

Submitted: 2016-08-15 03:36:44; Last Modified: 2016-08-15 11:33:05.