A195311 Row sums of A195310.

0, 1, 3, 5, 7, 10, 13, 17, 21, 25, 29, 33, 38, 43, 48, 54, 60, 66, 72, 78, 84, 90, 97, 104, 111, 118, 126, 134, 142, 150, 158, 166, 174, 182, 190, 199, 208, 217, 226, 235, 245, 255, 265, 275, 285, 295, 305, 315, 325, 335, 345, 356, 367, 378, 389, 400

Offset: 1

Author

Omar E. Pol, Sep 21 2011

Keywords

• nonn

Examples

			If written as an irregular triangle in which row n has length A026741(n+1) then the first differences in row n are always n (see below).
Triangle begins:
0,
1,3,5,
7,10,
13,17,21,25,29,
33,38,43,
48,54,60,66,72,78,84,
90,97,104,111,
118,126,134,142,150,158,166,174,182,
190,199,208,217,226,
235,245,255,265,275,285,295,305,315,325,335,
345,356,367,378,389,400
		

Crossrefs

Cf. A001318, A026741, A195309, A195310.

Programs

Mathematica

a1318[n_] := If[EvenQ[n], n (3 n/2 + 1)/4, (n + 1) (3 n + 1)/8];
a[n_] := DeleteCases[Table[n - a1318[k], {k, 1, n}], _?Negative] // Total;
Array[a, 56] (* Jean-François Alcover, Jun 26 2019 *)

Sage

def A195311(n):
    return add(max(0,n-k*(3*k-1)/2)+max(0,n-k*(3*k+1)/2) for k in (1..n))
[A195311(n) for n in (1..56)]  # Peter Luschny, Oct 12 2012