OFFSET
2,3
LINKS
Giovanni Resta, Table of n, a(n) for n = 2..1000
MATHEMATICA
a[2]=1; a[n_] := Block[{c = 0, nb = 0}, While[c == 0, c = Count[2^n - 1 - Total /@ Subsets[2^Range[n - 2], {nb}], x_ /; PrimeQ[x]]; nb++]; c]; a /@ Range[2, 85] (* Giovanni Resta, Apr 09 2020 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Apr 08 2020
EXTENSIONS
Terms a(35) and beyond from Giovanni Resta, Apr 09 2020
STATUS
approved