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A303577 Break up the list of values of the divisor function d(k) into nondecreasing runs; sequence gives lengths of successive runs. 3
4, 2, 2, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 4, 4, 2, 3, 1, 2, 2, 2, 2, 2, 2, 2, 4, 2, 2, 2, 2, 4, 2, 2, 1, 1, 2, 4, 2, 2, 4, 4, 2, 3, 1, 2, 2, 2, 2, 3, 3, 4, 2, 2, 2, 2, 4, 2, 2, 4, 4, 2, 2, 2, 2, 4, 2, 3, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 2, 4, 2, 2, 4, 4, 2, 2, 4, 4, 2, 2, 1, 1, 2, 4, 2, 2, 2, 2, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..10000

EXAMPLE

The initial values of d(k) = A000005(k) for k = 1,2,3,... are

1, 2, 2, 3, 2, 4, 2, 4, 3, 4, 2, 6, 2, 4, 4, 5, 2, 6, 2, 6, 4, 4, 2, 8, 3, 4, 4, 6, 2, 8, 2, 6, 4, 4, 4, 9, 2, 4, 4, 8, 2, 8, 2, 6, 6, 4, 2, 10, 3, 6, 4, 6, 2, 8, 4, 8, 4, 4, 2, 12, 2, 4, 6, 7, 4, 8, 2, 6, 4, 8, 2, 12, 2, 4, 6, 6, 4, 8, 2, ...

Breaking this up into nondecreasing runs we get:

[1, 2, 2, 3], [2, 4], [2, 4], [3, 4], [2, 6], [2, 4, 4, 5], [2, 6], [2, 6], [4, 4], [2, 8], [3, 4, 4, 6], [2, 8], [2, 6], [4, 4, 4, 9], [2, 4, 4, 8], [2, 8], [2, 6, 6], [4], [2, 10], [3, 6], [4, 6], [2, 8], [4, 8], [4, 4], [2, 12], [2, 4, 6, 7], ...

whose successive lengths are

4,2,2,2,2,4,2,2,2,2,4,2,2,4,4,2,3,1,2,...

CROSSREFS

Cf. A000005.

A303578(m) gives value of n that starts the m-th run.

A284597(m) is the smallest number that starts a run of length m.

Sequence in context: A136714 A280135 A297825 * A010314 A080133 A054575

Adjacent sequences:  A303574 A303575 A303576 * A303578 A303579 A303580

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Apr 29 2018

EXTENSIONS

More terms from Seiichi Manyama, Apr 29 2018

STATUS

approved

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Last modified June 2 11:20 EDT 2020. Contains 334771 sequences. (Running on oeis4.)