login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

a(n)-th Fibonacci number is the smallest Fibonacci number containing exactly n 5's.
0

%I #5 Apr 26 2017 16:39:28

%S 5,10,60,85,124,125,207,167,211,275,295,335,416,391,435,405,472,516,

%T 555,625,663,693,634,799,821,765,842,840,850,1048,975,1037,851,1207,

%U 977,1302,1194,1306,1182,1185,1466,1549,1237,1567,1585,1485,1700,1656,1636

%N a(n)-th Fibonacci number is the smallest Fibonacci number containing exactly n 5's.

%e a(2)=10 since 10th Fibonacci number i.e. 55 contains exactly two 5's.

%Y Cf. A000045.

%K base,nonn

%O 1,1

%A _Shyam Sunder Gupta_, Jul 14 2002

%E a(21)-a(49) from _Alois P. Heinz_, Apr 26 2017