a(n) is the number of subsets of {1,...,n} containing no solutions to x+y=z with x and y distinct (one version of "sum-free subsets").

A085489

a(n) is the number of subsets of {1,...,n} containing no solutions to x+y=z with x and y distinct (one version of "sum-free subsets").

Terms

    a(0) =1a(1) =2a(2) =4a(3) =7a(4) =13a(5) =22a(6) =37a(7) =61a(8) =102a(9) =162a(10) =261a(11) =410a(12) =646a(13) =1001a(14) =1553a(15) =2370a(16) =3645a(17) =5515a(18) =8303a(19) =12470a(20) =18713a(21) =27811a(22) =41244a(23) =60962a(24) =89733a(25) =131870a(26) =192522a(27) =281125a(28) =408680a(29) =593880

External references