|
|
A139586
|
|
Non-Fibonacci numbers with Fibonacci number of divisors.
|
|
1
|
|
|
4, 7, 9, 11, 16, 17, 19, 23, 24, 25, 29, 30, 31, 37, 40, 41, 42, 43, 47, 49, 53, 54, 56, 59, 61, 66, 67, 70, 71, 73, 78, 79, 81, 83, 88, 97, 101, 102, 103, 104, 105, 107, 109, 110, 113, 114, 121, 127, 128, 130, 131, 135, 136, 137, 138
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
A000005(a(n)) is a Fibonacci number.
|
|
LINKS
|
|
|
EXAMPLE
|
16 is a term because it is not a Fibonacci number and its number of divisors is 5, a Fibonacci number.
|
|
MATHEMATICA
|
fibs=Fibonacci[Range[15]]; nonfibs=Complement[Range[fibs[[-1]]], fibs]; Select[nonfibs, MemberQ[fibs, DivisorSigma[0, #]]&] (* Harvey P. Dale, Jan 11 2011 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|