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A271750
a(1) = 1; a(n+1) = smallest Fibonacci number > a(n) with leading digit equal to the final digit of a(n).
1
1, 13, 34, 4181, 10946, 63245986, 6557470319842, 27777890035288, 806515533049393, 3416454622906707, 7540113804746346429, 927372692193078999176, 6356306993006846248183, 3311648143516982017180081, 14028366653498915298923761, 155576970220531065681649693, 30960598847965113057878492344
OFFSET
1,2
COMMENTS
Look at this array:
...1
...13
....34
.....4181
........10946
............63245986
...................6557470319842
.
.
.
................................34507973060837282187130139035400899082304280
Since no positive Fibonacci number begins with 0, the sequence ends here.
- N. J. A. Sloane, May 02 2016
LINKS
EXAMPLE
Since a(1) = 1, a(2) must start with 1 and so a(2) = 13;
since a(2) = 13, a(3) must start with 3, and so a(3) = 34;
since a(3) = 34, a(4) must start with 4 and the smallest Fibonacci number greater than 34 and beginning with 4 is 4181; ...
MATHEMATICA
F = Fibonacci; L={2}; While[(d = Mod[F[k = Last@L], 10]) > 0, While[ IntegerDigits[ F[++k]][[1]] != d]; AppendTo[L, k]]; F@L (* Giovanni Resta, May 02 2016 *)
CROSSREFS
Cf. A061448.
Sequence in context: A214729 A280322 A262851 * A082214 A115161 A063300
KEYWORD
nonn,base,fini,full
AUTHOR
STATUS
approved