OFFSET
1,3
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
A000161(a(n)) = 1. - R. J. Mathar, Nov 29 2006
MATHEMATICA
Select[Range[0, 300], !PrimeQ[#] && Length @ PowersRepresentations[#, 2, 2] == 1 &] (* Amiram Eldar, Mar 12 2020 *)
PROG
(PARI) A000161(n)={ local(cnt=0, y2) ; for(x=0, floor(sqrt(n)), y2=n-x^2 ; if( y2>=x^2 && issquare(y2), cnt++ ; ) ; ) ; return(cnt) ; } isA124982(n)= { if( isprime(n), return(0), if(A000161(n)==1, return(1), return(0) ) ) ; } { for(n=0, 300, if( isA124982(n), print1(n, ", ") ; ) ; ) ; } \\ R. J. Mathar, Nov 29 2006
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Nov 16 2006
EXTENSIONS
Corrected and extended by R. J. Mathar, Nov 29 2006
STATUS
approved