A045702 - OEIS

A045702

Sums of two squares of Fibonacci numbers.

0, 1, 2, 4, 5, 8, 9, 10, 13, 18, 25, 26, 29, 34, 50, 64, 65, 68, 73, 89, 128, 169, 170, 173, 178, 194, 233, 338, 441, 442, 445, 450, 466, 505, 610, 882, 1156, 1157, 1160, 1165, 1181, 1220, 1325, 1597, 2312, 3025, 3026, 3029, 3034, 3050, 3089, 3194, 3466

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

Index entries for sequences related to sums of squares

FORMULA

a(4)=5 because 5 = 1^2 + 2^2;

a(8)=13 because 13 = 2^2 + 3^2.

MATHEMATICA

Take[Union[Total/@Tuples[Fibonacci[Range[0, 15]]^2, {2}]], 60] (* Harvey P. Dale, Jan 17 2011 *)

PROG

(PARI) list(lim)=my(sq=sqrtint(lim\=1), v=List(), f=List([0, 1]), t); while((t=f[#f]+f[#f-1])<=sq, listput(f, t)); f=apply(sqr, f); for(i=1, #f, for(j=1, i, t=f[i]+f[j]; if(t>lim, break); listput(v, t))); Set(v) \\ Charles R Greathouse IV, Jun 27 2017

CROSSREFS

Sequence in context: A069011 A353386 A101185 * A005658 A166021 A339906

Adjacent sequences: A045699 A045700 A045701 * A045703 A045704 A045705

KEYWORD

nonn,easy,nice

AUTHOR

Felice Russo

STATUS

approved