Number of subsets of { 1, ..., n } containing an A.P. of length 10.

Terms

a(0) =0a(1) =0a(2) =0a(3) =0a(4) =0a(5) =0a(6) =0a(7) =0a(8) =0a(9) =0a(10) =1a(11) =3a(12) =8a(13) =20a(14) =48a(15) =112a(16) =256a(17) =576a(18) =1280a(19) =3280a(20) =7968a(21) =17840a(22) =39487a(23) =86587a(24) =188396a(25) =407230a(26) =875320a(27) =1872332a(28) =4218648a(29) =9382099