|
| |
| |
|
|
|
1, 2, 2, 3, 3, 3, 5, 6, 7, 7, 7, 7, 7, 9, 9, 10, 12, 13, 13, 13, 13, 13, 15, 15, 16, 16, 16, 18, 18, 18, 20, 21, 21, 23, 23, 24, 24, 24, 24, 24, 26, 26, 26, 26, 26, 28, 30, 30, 33, 34, 34, 34, 34, 34, 34, 36, 36, 36, 36, 36, 36, 38, 40, 41, 41, 41, 41, 43, 43, 43, 45, 46, 48, 48
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
Table of n, a(n) for n=1..74.
M. Baake and R. V. Moody, Similarity submodules and root systems in four dimensions, Canad. J. Math. 51 (1999), 1258-1276.
|
|
|
FORMULA
|
a(n) = Sum_{k=1..n} A035185(k);
a(n) is asymptotic to c*n where c = log(1+sqrt(2))/sqrt(2) = 0.62322524014023051339402008...
a(n) = Sum_{k=1..n} K(k,2)*floor(n/k) where K(x,y) is the Kronecker symbol. - Benoit Cloitre, Oct 31 2009
|
|
|
MATHEMATICA
|
Table[DivisorSum[n, KroneckerSymbol[2, #]&], {n, 1, 100}] // Accumulate (* Jean-François Alcover, Nov 11 2018 *)
|
|
|
PROG
|
(PARI) a(n)=sum(k=1, n, kronecker(k, 2)*floor(n/k)) \\ Benoit Cloitre, Oct 31 2009
|
|
|
CROSSREFS
|
Cf. A035185, A078428.
Sequence in context: A240519 A318037 A326165 * A239518 A293924 A307730
Adjacent sequences: A078459 A078460 A078461 * A078463 A078464 A078465
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
Benoit Cloitre, Dec 31 2002
|
|
|
EXTENSIONS
|
Corrected by T. D. Noe, Nov 02 2006
|
|
|
STATUS
|
approved
|
| |
|
|
