|
|
A275649
|
|
Number of squarefree odd numbers k > 1 less than 10^n such that k is a sum of two squares.
|
|
3
|
|
|
2, 14, 112, 997, 8982, 82305, 764092, 7159654, 67581778, 641696858, 6122456540, 58649349611, 563729377405, 5434188304040, 52515178669973, 508607849995010
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
This sequence gives the values of the counting function U(x), whose values are given in table 2 on page 359 of Shiu, 1986.
|
|
LINKS
|
|
|
MATHEMATICA
|
Table[Count[Range[1, 10^n, 2], k_ /; SquareFreeQ@ k && SquaresR[2, k] > 0], {n, 6}] (* Michael De Vlieger, Aug 04 2016 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,more
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|