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A248556
Concatenate (3n-2,3n-1,3n).
0
123, 456, 789, 101112, 131415, 161718, 192021, 222324, 252627, 282930, 313233, 343536, 373839, 404142, 434445, 464748, 495051, 525354, 555657, 585960, 616263, 646566, 676869, 707172, 737475, 767778, 798081, 828384, 858687, 888990, 919293, 949596, 979899
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
Sequence in context: A235133 A179612 A091331 * A031689 A181679 A193251
KEYWORD
nonn,base,easy
AUTHOR
Charles Duvall, Oct 08 2014
EXTENSIONS
More terms from Vincenzo Librandi, Oct 21 2014
STATUS
approved