A369392 - OEIS

%I #11 Jan 25 2024 08:03:25

%S 1,1,2,3,5,9,18,32,56,111,211,386,727,1374,2654,5018,9346,17946,33654,

%T 63754,120619,229835,443058,834608,1563645,2999088,5843122,11070802,

%U 21253933,41347141,79197559,153735211,293761934,570421574,1112023166,2153293449

%N Number of subsets of {2..n} such that the product of the elements plus 1 is a prime.

%e a(5) = 9 subsets: {}, {2}, {4}, {2, 3}, {2, 5}, {3, 4}, {2, 3, 5}, {2, 4, 5} and {3, 4, 5}.

%Y Cf. A000040, A127542.

%K nonn

%O 0,3

%A _Ilya Gutkovskiy_, Jan 22 2024

%E a(22)-a(35) from _Alois P. Heinz_, Jan 22 2024