A134069 Primes in A038399.

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

Table of n, a(n) for n=1..3.

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

Adjacent sequences: A134066 A134067 A134068 * A134070 A134071 A134072

Keyword

bref,hard,more,nonn,base

Author

Alexander Adamchuk, Oct 06 2007

Status

approved