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A072675
Integers m such that the last digit of Fibonacci(m) is 1.
3
1, 2, 8, 19, 22, 28, 41, 59, 61, 62, 68, 79, 82, 88, 101, 119, 121, 122, 128, 139, 142, 148, 161, 179, 181, 182, 188, 199, 202, 208, 221, 239, 241, 242, 248, 259, 262, 268, 281, 299, 301, 302, 308, 319, 322, 328, 341, 359, 361, 362, 368, 379, 382, 388, 401
OFFSET
1,2
FORMULA
Sequence contains numbers of form (1+60k) (2+60k) (8+60k) (19+60k) (22+60k) (28+60k) (41+60k) (59+60k) k>=0.
G.f.: x*(x^8+18*x^7+13*x^6+6*x^5+3*x^4+11*x^3+6*x^2+x+1) / (x^9-x^8-x+1). - Colin Barker, Jun 16 2013
EXAMPLE
Fibonacci(28) = 317811, so 28 is a term.
MATHEMATICA
Position[Fibonacci[Range[500]], _?(Mod[#, 10]==1&)]//Flatten (* or *) LinearRecurrence[{1, 0, 0, 0, 0, 0, 0, 1, -1}, {1, 2, 8, 19, 22, 28, 41, 59, 61}, 70] (* Harvey P. Dale, Sep 17 2018 *)
CROSSREFS
Sequence in context: A306616 A372223 A183183 * A033711 A093012 A049525
KEYWORD
nonn,base,easy
AUTHOR
Benoit Cloitre, Aug 07 2002
STATUS
approved