Least triangular number representable as a sum of n consecutive triangular numbers, or -1 if no such triangular number exists.

A238017

Least triangular number representable as a sum of n consecutive triangular numbers, or -1 if no such triangular number exists.

Terms

    a(0) =0a(1) =1a(2) =10a(3) =10a(4) =55a(5) =-1a(6) =210a(7) =120a(8) =120a(9) =1485a(10) =2145a(11) =-1a(12) =2080a(13) =-1a(14) =-1a(15) =56616a(16) =1326a(17) =12561a(18) =-1a(19) =1540a(20) =1540a(21) =21736a(22) =-1a(23) =-1a(24) =52650a(25) =16653a(26) =4950a(27) =26796a(28) =10440a(29) =12880

External references