|First digit-last digit| for triangular numbers.
0, 0, 0, 0, 1, 4, 1, 6, 3, 1, 0, 0, 1, 8, 4, 1, 5, 2, 0, 1, 2, 1, 1, 4, 3, 2, 2, 5, 2, 1, 1, 2, 3, 4
2 seqfan posts
Fri May 21 18:12:30 CEST 2010 [seqfan] Re: Comments and corrections: A122811 and A059975