Number of nonempty subsets of {1, 2, ..., n} with GCD equal to 1 and containing the sum of any two elements whenever it is at most n.

A358392

Number of nonempty subsets of {1, 2, ..., n} with GCD equal to 1 and containing the sum of any two elements whenever it is at most n.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =9a(6) =19a(7) =27a(8) =46a(9) =63a(10) =113a(11) =148a(12) =253a(13) =345a(14) =539a(15) =734a(16) =1198a(17) =1580a(18) =2540a(19) =3417a(20) =5233a(21) =7095a(22) =11190a(23) =14720a(24) =22988a(25) =31057a(26) =47168a(27) =63331a(28) =98233a(29) =129836

External references