OFFSET
1,1
COMMENTS
Golden rectangle numbers equal the partial sums of squares of Fibonacci numbers.
Corresponding golden rectangle numbers are 15, 4895, 1576239, 507544127, 163427632719, 52623190191455, ...
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..10000
EXAMPLE
4 is a term because 1^2 + 1^2 + 2^2 + 3^2 = 3*5 = x^2 + y^2 + z^2 has no solution for integer x, y and z.
5 is not a term because 1^2 + 1^2 + 2^2 + 3^2 + 5^2 = 5*8 = 2^2 + 6^2.
PROG
(PARI) isA004215(n)= my(fouri, j) ; fouri=1 ; while( n >=7*fouri, if( n % fouri ==0, j= n/fouri-7 ; if( j % 8==0, return(1) ) ; ); fouri *= 4 ; ) ; return(0) ;
a001654(n) = fibonacci(n)*fibonacci(n+1);
for(n=1, 1e3, if(isA004215(a001654(n)), print1(n, ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Altug Alkan, Mar 08 2016
STATUS
approved