login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A071006 Number of positive solutions to the Diophantine equation x^2+y^3=n^2 with y <= x. 1
0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 2, 0, 1, 0, 0, 1, 0, 1, 2, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,55
LINKS
MAPLE
f:= proc(n) local t, v, y;
t:= 0:
for y from 1 do
v:= n^2 - y^3;
if v < y^2 then return t fi;
if issqr(v) then t:= t+1 fi
od
end proc:
map(f, [$1..100]); # Robert Israel, Jun 25 2024
PROG
(PARI) for(n=1, 100, print1(sum(i=1, n, sum(j=1, i, if(i^2+j^3-n^2, 0, 1))), ", "))
CROSSREFS
Cf. A078359.
Sequence in context: A191250 A107064 A113687 * A227740 A284503 A281455
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, May 18 2002
EXTENSIONS
Name clarified by Sean A. Irvine, Jun 25 2024
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 4 20:04 EDT 2024. Contains 375685 sequences. (Running on oeis4.)