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A273045
Fibonacci numbers with digits in nondecreasing order.
2
0, 1, 1, 2, 3, 5, 8, 13, 34, 55, 89, 144, 233, 377
OFFSET
1,4
COMMENTS
Intersection of A000045 and A009994. - Felix Fröhlich, May 16 2016
Conjecture: The sequence is finite, with 377 being the last term. I have verified the conjecture up to A000045(10^5). - Felix Fröhlich, May 16 2016
Conjecture verified up to Fibonacci(10^8). - Charles R Greathouse IV, May 17 2016
MATHEMATICA
Select[Fibonacci@ Range[0, 10^4], Sort@ # == # &@ IntegerDigits@ # &] (* Michael De Vlieger, May 13 2016 *)
PROG
(PARI) is_a009994(n) = digits(n)==vecsort(digits(n))
for(n=0, 1e4, if(is_a009994(fibonacci(n)), print1(fibonacci(n), ", "))) \\ Felix Fröhlich, May 16 2016
(PARI) fibmod(n, m)=lift(((Mod([1, 1; 1, 0], m))^n)[1, 2])
isA009994(n)=my(d=digits(n)); vecsort(d)==d
B1=10^9; B2=10^57;
for(n=1, 1e9, if(isA009994(fibmod(n, B1)) && isA009994(fibmod(n, B2)) && isA009994(F=fibonacci(n)), print1(F", "))) \\ Charles R Greathouse IV, May 17 2016
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Omar E. Pol, May 13 2016
EXTENSIONS
Offset adjusted by Felix Fröhlich, May 16 2016
STATUS
approved