Triangular numbers n with digits d_1, d_2, ..., d_k such that d_1*(d_1+1)/2 + ... + d_k*(d_k+1)/2 is a triangular number.
A254957
Triangular numbers n with digits d_1, d_2, ..., d_k such that d_1*(d_1+1)/2 + ... + d_k*(d_k+1)/2 is a triangular number.
Terms
- a(0) =0a(1) =1a(2) =3a(3) =6a(4) =10a(5) =136a(6) =231a(7) =300a(8) =3160a(9) =3741a(10) =4371a(11) =5565a(12) =5995a(13) =6328a(14) =6555a(15) =10011a(16) =10440a(17) =10731a(18) =13366a(19) =13530a(20) =14196a(21) =18528a(22) =19900a(23) =20301a(24) =21115a(25) =23220a(26) =25200a(27) =25651a(28) =30135a(29) =30628
External references
- oeis: A254957