A134554 Concatenate the terms of three copies of the Fibonacci sequence.

0, 111, 111, 222, 333, 555, 888, 131313, 212121, 343434, 555555, 898989, 144144144, 233233233, 377377377, 610610610, 987987987, 159715971597, 258425842584, 418141814181, 676567656765, 109461094610946, 177111771117711

Offset: 0

Author

Deuard Worthen (deuard(AT)tx.rr.com), Jan 23 2008, at the suggestion of N. J. A. Sloane

Keywords

• nonn
• base
• easy

Comments

Leading zeros are omitted.

Crossrefs

Cf. A000045, A074842.

Programs

Maple

catL := proc(i,j) i*10^(max(1,ilog10(j)+1))+j ; end: Fib := proc(n) if n = 0 then 0 ; else combinat[fibonacci](n+1) ; fi ; end: A134554 := proc(n) local f ; f := Fib(n) ; catL( catL(f,f),f) ; end: seq(A134554(n),n=0..25) ; # R. J. Mathar, Jan 29 2008
with(combinat): concat:=proc(a,b) local bb: bb:=nops(convert(b,base,10)): 10^bb*a+b end proc: seq(concat(fibonacci(p),concat(fibonacci(p),fibonacci(p))),p=1..20); # Emeric Deutsch, Jan 29 2008

Mathematica

concatfib[n_]:=Module[{idn=IntegerDigits[n]},FromDigits[Join[idn,idn,idn]]]; concatfib/@Fibonacci[Range[0,30]] (* Harvey P. Dale, Jul 13 2015 *)

Formula

a(n)=A074842(A000045(n+1)). - R. J. Mathar, Jan 29 2008

Extensions

More terms from R. J. Mathar and Emeric Deutsch, Jan 29 2008