Number of subsets of 6 integers between 1 and n such that their sum is 0 modulo n.

Terms

a(0) =1a(1) =3a(2) =10a(3) =20a(4) =42a(5) =76a(6) =132a(7) =212a(8) =335a(9) =497a(10) =728a(11) =1028a(12) =1428a(13) =1932a(14) =2586a(15) =3384a(16) =4389a(17) =5601a(18) =7084a(19) =8844a(20) =10966a(21) =13442a(22) =16380a(23) =19780a(24) =23751a(25) =28301a(26) =33566a(27) =39536a(28) =46376a(29) =54086