a(n) = number of subsets S of {1,2,...,n} having more than 2 elements such that (sum of least two elements of S) = difference between greatest two elements of S.
A357292
a(n) = number of subsets S of {1,2,...,n} having more than 2 elements such that (sum of least two elements of S) = difference between greatest two elements of S.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =1a(6) =2a(7) =5a(8) =11a(9) =23a(10) =47a(11) =96a(12) =193a(13) =388a(14) =778a(15) =1558a(16) =3118a(17) =6239a(18) =12480a(19) =24963a(20) =49929a(21) =99861a(22) =199725a(23) =399454a(24) =798911a(25) =1597826a(26) =3195656a(27) =6391316a(28) =12782636a(29) =25565277
External references
- oeis: A357292