A246315 A246314(2^n-1).
1, 9, 37, 157, 713, 2737, 11421, 44021, 176801, 683369, 2695829, 10433229, 40796217
Offset: 0
Examples
a(1)=9 and a(2)=37 are illustrated in A246314.
Crossrefs
Cf. A246314.
Extensions
a(9) from Alois P. Heinz, Sep 01 2014
a(10)-a(12) from N. J. A. Sloane, Sep 04 2014