A339576 Row sums of triangle A236104.

1, 4, 10, 17, 29, 41, 59, 74, 101, 121, 151, 179, 215, 245, 295, 326, 374, 423, 477, 519, 591, 641, 707, 767, 844, 904, 1000, 1056, 1140, 1234, 1324, 1387, 1507, 1587, 1701, 1794, 1902, 1992, 2136, 2226, 2346, 2476, 2602, 2692, 2874, 2984, 3122, 3246, 3397

Offset: 1

Author

N. J. A. Sloane, Dec 18 2020

Keywords

• nonn

Comments

In other words, a(n) is the sum of squares of terms in row n of A235791.

Crossrefs

Cf. A024916, A060831, A235791, A236104, A237593, A240542.

Programs

Maple

a:= n-> add(ceil((n+1)/k-(k+1)/2)^2, k=1..floor((sqrt(8*n+1)-1)/2)):
seq(a(n), n=1..60);  # Alois P. Heinz, Dec 18 2020

PARI

a(n) = sum(k=1, floor((sqrt(8*n+1)-1)/2), ceil((n+1)/k-(k+1)/2)^2) \\ Felix Fröhlich, Dec 19 2020; adapted from Maple code