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A136743 Number of prime factors in the n-th run of squarefree numbers. 7
2, 4, 3, 5, 1, 1, 5, 2, 5, 6, 5, 5, 3, 2, 1, 2, 5, 3, 6, 6, 3, 6, 3, 6, 1, 2, 6, 1, 5, 6, 6, 6, 4, 4, 1, 6, 4, 5, 6, 4, 1, 1, 5, 5, 2, 1, 6, 3, 4, 5, 6, 7, 4, 6, 1, 1, 6, 4, 7, 6, 6, 6, 3, 7, 1, 2, 6, 1, 5, 2, 1, 7, 6, 3, 7, 1, 1, 5, 3, 5, 8, 5, 1, 2, 4, 6, 2, 1, 6, 3, 6, 7, 4, 7, 4, 1, 2, 2, 6, 1, 6, 6, 2, 6, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) = A001221(A136742(n)) = A001222(A136742(n));

a(A136744(n)) = n and a(m) <> n for m < A136744(n).

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..1000

Eric Weisstein's World of Mathematics, Squarefree

FORMULA

a(n) = SUM(A001221(A072284(n)+k): 0<=k < A120992(n)).

EXAMPLE

a(10)=A001221(A136742(10))=A001221(39270)=A001221(2*3*5*7*11*17)=6.

CROSSREFS

Cf. A005117.

Sequence in context: A178938 A228196 A261326 * A011387 A019656 A256751

Adjacent sequences:  A136740 A136741 A136742 * A136744 A136745 A136746

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jan 20 2008

STATUS

approved

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Last modified June 19 19:11 EDT 2019. Contains 324222 sequences. (Running on oeis4.)