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A117704
Least refined sequence that can be grouped to sum to either natural numbers or odd numbers.
2
1, 2, 1, 2, 3, 1, 5, 1, 5, 4, 3, 8, 9, 4, 6, 9, 2, 12, 3, 10, 9, 5, 15, 1, 15, 8, 9, 16, 2, 19, 6, 14, 15, 6, 22, 3, 20, 13, 11, 24, 1, 26, 10, 17, 22, 6, 29, 6, 24, 19, 12, 32, 1, 32, 15, 19, 30, 5, 36, 10, 27, 26, 12, 39, 4, 36, 21, 20, 39, 3, 43, 15, 29, 34, 11, 46, 8, 39, 28, 20, 49, 50
OFFSET
1,2
COMMENTS
In other words, least common refinement of the natural numbers and the odd numbers.
LINKS
FORMULA
a(n) = A005214(n) - A005214(n-1).
EXAMPLE
As natural numbers: 1,2,1+2,3+1,5,1+5,4+3,8,...
As odd numbers: 1,2+1,2+3,1+5+1,5+4,3+8,...
PROG
(Haskell)
a117704 n = a117704_list !! (n-1)
a117704_list = 1 : zipWith (-) (tail a005214_list) a005214_list
-- Reinhard Zumkeller, Aug 03 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved