If n = binomial(b,2) + binomial(c,1), b > c >= 0 then a(n) = binomial(b+1,3) + binomial(c+1,2).

Terms

a(0) =1a(1) =2a(2) =4a(3) =5a(4) =7a(5) =10a(6) =11a(7) =13a(8) =16a(9) =20a(10) =21a(11) =23a(12) =26a(13) =30a(14) =35a(15) =36a(16) =38a(17) =41a(18) =45a(19) =50a(20) =56a(21) =57a(22) =59a(23) =62a(24) =66a(25) =71a(26) =77a(27) =84a(28) =85a(29) =87