A333572 -id:A333572 - cp's OEIS frontend

A333573 a(n) = A333572(n)/4.

0, 1, 2, 3, 5, 7, 9, 12, 17, 20, 24, 28, 34, 37, 44, 49, 56, 63, 73, 79, 87, 94, 105, 110, 122, 132, 144, 153, 166, 177, 187, 199, 215, 225, 243, 252, 271, 282, 300, 314, 328, 343, 364, 379, 399, 413, 435, 448, 471, 490, 513, 530, 554, 572, 594, 613, 640, 657

Offset: 1

Hugo Pfoertner, Mar 27 2020

nonn

Robert Israel, Table of n, a(n) for n = 1..2000

Cf. A004018, A232705, A333462, A333572.

A333462 a(n) is the number of Gaussian integers z such that (n-1)/2 < |z| <= n/2, divided by 4.

Original entry on oeis.org

0, 1, 1, 1, 2, 2, 2, 3, 5, 3, 4, 4, 6, 3, 7, 5, 7, 7, 10, 6, 8, 7, 11, 5, 12, 10, 12, 9, 13, 11, 10, 12, 16, 10, 18, 9, 19, 11, 18, 14, 14, 15, 21, 15, 20, 14, 22, 13, 23, 19, 23, 17, 24, 18, 22, 19, 27, 17, 26, 22, 28, 17, 31, 21, 26, 24, 28, 26, 30, 27, 29, 21

Offset: 1

Hugo Pfoertner, Mar 26 2020

nonn

Hugo Pfoertner, Table of n, a(n) for n = 1..10000

Cf. A004018, A232705, A333572, A333573.

c=vectorsmall(2000000);for(x=1,1000,my(x2=x*x);c[x2]++;c[x2+x2]++;for(y=1,x-1,my(y2=y*y);c[x2+y2]+=2));
a(n)=sum(k=ceil((1+(n-1)^2)/4),floor(n^2/4),c[k]);
for(k=1,72,print1(a(k),", "))

cp's OEIS Frontend

A333573 a(n) = A333572(n)/4.

Views

Author

Keywords

Links

Crossrefs