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A134069
Primes in A038399.
3
11, 211, 853211
OFFSET
1,1
COMMENTS
A038399 = {1, 11, 211, 3211, 53211, 853211, 13853211, 2113853211, ...} = concatenation of first n nonzero Fibonacci numbers in reverse order.
From Robert Israel, Sep 14 2016: (Start)
No more terms < A038399(500), which has 26252 digits.
The probability of a number of the order of magnitude of A038399(n) being prime is approximately constant/n^2. Since Sum_n 1/n^2 converges, we should expect this sequence to be finite. (End)
LINKS
Eric Weisstein's World of Mathematics, Fibonacci Number
Eric Weisstein's World of Mathematics, Smarandache Sequences
MAPLE
count:= 0:
A038399[1]:= 1:
for n from 2 to 100 do
A038399[n]:= combinat:-fibonacci(n)*10^(1+ilog10(A038399[n-1]))+A038399[n-1];
if isprime(A038399[n]) then count:= count+1; A[count]:= A038399[n] fi
od:
seq(A[i], i=1..count); # Robert Israel, Sep 14 2016
MATHEMATICA
Module[{nn=10, bif}, bif=Fibonacci[Range[nn]]; Select[Table[FromDigits[ Flatten[ IntegerDigits/@Reverse[Take[bif, n]]]], {n, nn}], PrimeQ]] (* Harvey P. Dale, Sep 27 2019 *)
CROSSREFS
Cf. A038399 (concatenation of first n nonzero Fibonacci numbers in reverse order).
Cf. A019523 (concatenation of Fibonacci numbers).
Sequence in context: A114758 A088061 A070220 * A137464 A357915 A187650
KEYWORD
bref,hard,more,nonn,base
AUTHOR
Alexander Adamchuk, Oct 06 2007
STATUS
approved