Post #2021684

@christianp the differences 2,4,4,5,9 do appear multiple times. :) To me these seem like they are close to the triangular numbers. a(1) = 1 = T_1 a(2) = 3 = T_2 a(3) = 7 = T_3 + T_1 a(4) = 11 = T_4 + T_1 a(5) = 16 = T_5 + T_1 a(6) = 25 = T_6 + T_2 + T_1 Guess is a(7) = 32 = T_7 + T_2 + T_1 a(8) = 40 = T_8 + T_2 + T_1 a(9) = 55 = T_9 + T_3 + T_2 + T_1 ? But I am also guessing that is just coincidence. I spent too long looking at https://oeis.org/A327629 to see if its partial sums had some reasonable interpretation.