A078428 Partial sums of A035187.

1, 1, 1, 2, 3, 3, 3, 3, 4, 4, 6, 6, 6, 6, 6, 7, 7, 7, 9, 10, 10, 10, 10, 10, 11, 11, 11, 11, 13, 13, 15, 15, 15, 15, 15, 16, 16, 16, 16, 16, 18, 18, 18, 20, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22, 24, 24, 24, 24, 26, 26, 28, 28, 28, 29, 29, 29, 29, 29, 29, 29, 31, 31, 31, 31, 31, 33

Offset: 0

Author

Benoit Cloitre, Dec 29 2002

Keywords

• nonn

Links

• M. Baake, Algebra, Combinatorics and Number Theory
• M. Baake and R. V. Moody, Similarity submodules and root systems in four dimensions, arXiv:math/9904028 [math.MG], 1999; Canad. J. Math. 51 (1999), 1258-1276.

Programs

Mathematica

Array[DivisorSum[#, KroneckerSymbol[5, #]&]&, 76] // Accumulate (* Jean-François Alcover, Dec 13 2018 *)

Formula

a(n) = Sum_{k=1..n} A035187(k).

a(n) is asymptotic to c*n where c=2*log(tau)/sqrt(5) and tau=(1+sqrt(5))/2