A134072 Concatenation of A000204 Lucas numbers (beginning at 1) in reverse order.

1, 31, 431, 7431, 117431, 18117431, 2918117431, 472918117431, 76472918117431, 12376472918117431, 19912376472918117431, 32219912376472918117431, 52132219912376472918117431, 84352132219912376472918117431

Offset: 1

Author

Alexander Adamchuk, Oct 06 2007

Keywords

• nonn
• base

Comments

Indices of prime terms are {2, 3, 5, 11, ...}. Primes are listed in A134071 = {31, 431, 117431, 19912376472918117431, ...}.

Links

• Eric Weisstein's World of Mathematics, Lucas Number
• Eric Weisstein's World of Mathematics, Smarandache Sequences

Crossrefs

Cf. A000204 (Lucas numbers).

Cf. A130774 (concatenation of Lucas numbers).

Cf. A019523 (concatenation of Fibonacci numbers).

Cf. A038399 (concatenation of first n nonzero Fibonacci numbers in reverse order).

Cf. A134069 (primes in A038399).

Cf. A134070 (primes in A130774).

Cf. A134071 (primes in A134072).

Programs

Mathematica

Module[{nn=20,lnos},lnos=LucasL[Range[nn]];Table[FromDigits[Flatten[ IntegerDigits/@ Reverse[Take[lnos,n]]]],{n,nn}]] (* Harvey P. Dale, Jul 27 2015 *)

Extensions

Edited by Charles R Greathouse IV, Apr 26 2010