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A225843
Integral parts of sums of the reciprocals of the Collatz (3x+1) sequence starting with n.
3
1, 1, 2, 1, 2, 2, 2, 1, 3, 2, 2, 2, 2, 2, 2, 1, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 1, 3, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3
OFFSET
1,3
COMMENTS
a(n) = floor(sum(1/A070165(n,k): k = 1..A006577(n)));
conjecture: a(n) <= 3;
a(n) = 1 iff n = 2^k: a(A000079(n)) = 1, a(A057716(n)) > 1.
FORMULA
a(n) = floor(A225761(n)/A225784(n)).
PROG
(Haskell)
a225843 = floor . sum . map (recip . fromIntegral) . a070165_row
CROSSREFS
Sequence in context: A023588 A175242 A355770 * A327657 A301957 A318874
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 16 2013
STATUS
approved