a(n) = number of grid points that are covered after (2^n)th stage of A139250.

A160128

a(n) = number of grid points that are covered after (2^n)th stage of A139250.

Terms

    a(0) =3a(1) =7a(2) =19a(3) =63a(4) =235a(5) =919a(6) =3651a(7) =14575a(8) =58267a(9) =233031a(10) =932083a(11) =3728287a(12) =14913099a(13) =59652343a(14) =238609315a(15) =954437199a(16) =3817748731a(17) =15270994855a(18) =61083979347a(19) =244335917311a(20) =977343669163

External references