OFFSET
1,1
MAPLE
conc3:= (a, b, c) -> c + 10^(1+ilog10(c))*(b+10^(1+ilog10(b))*a):
seq(conc3(3*k-2, 3*k-1, 3*k), k=1..100); # Robert Israel, Oct 23 2014
MATHEMATICA
FromDigits[Flatten[IntegerDigits/@{#}]]&/@Partition[Range[100], 3] (* Vincenzo Librandi, Oct 21 2014 *)
PROG
(Magma) [Seqint(Intseq(n+1) cat Intseq(n) cat Intseq(n-1)): n in [2..100 by 3]]; // Vincenzo Librandi, Oct 21 2014
(PARI) a(n)=eval(Str(3*n-2, 3*n-1, 3*n)) \\ M. F. Hasler, Oct 22 2014
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Charles Duvall, Oct 08 2014
EXTENSIONS
More terms from Vincenzo Librandi, Oct 21 2014
STATUS
approved