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A201208 One 1, two 2's, three 1's, four 2's, five 1's, ... 2
1, 2, 2, 1, 1, 1, 2, 2, 2, 2, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
a(n) = A057212(n) + 1. - T. D. Noe, Nov 28 2011
EXAMPLE
May be written as a triangle:
1
2 2
1 1 1
2 2 2 2
1 1 1 1 1
2 2 2 2 2 2
1 1 1 1 1 1 1
Row sums are A022998(n+1).
MATHEMATICA
ReplaceAll[ColumnForm[Table[Mod[k, 2], {k, 12}, {n, k}], Center], 0 -> 2] (* Alonso del Arte, Nov 28 2011 *)
PROG
(Haskell)
a201208 n = a201208_list !! (n-1)
a201208_list = concat $ zipWith ($) (map replicate [1..]) a000034_list
-- Reinhard Zumkeller, Dec 02 2011
CROSSREFS
Cf. A000034.
Sequence in context: A228825 A324381 A331383 * A006513 A105224 A261627
KEYWORD
nonn,tabl,easy
AUTHOR
Paul Curtz, Nov 28 2011
EXTENSIONS
Edited by N. J. A. Sloane, Dec 02 2011
STATUS
approved

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Last modified March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)