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A053146 When cototient function (A051953) is iterated with initial value A002110(n), a(n) = number of iterates that are not powers of 2. 0
1, 2, 4, 6, 12, 11, 25, 22, 32, 26, 54, 55, 67, 68, 85, 117, 126, 113, 150, 166, 130, 178, 186, 207, 201, 194, 253, 255, 256, 295, 284, 309, 320, 315, 348, 347, 365, 398, 423, 425, 433, 459, 468, 488 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

In these iteration chains, the numbers that are not powers of 2 seem to be in the majority.

LINKS

Table of n, a(n) for n=1..44.

EXAMPLE

n=6, A002110(6)=30030; the corresponding iteration chain is: {30030, 24270, 17806, 9238, 4798, 2400, 1760, 1120, 736, 384, 256, 128, 64, 32, 16, 8, 4, 2, 1, 0}. It has 20 terms, among which entries from the first to 10th, also the last 0, are not powers of 2, so a(6)=11.

CROSSREFS

Cf. A002110, A051953.

Sequence in context: A136103 A182235 A180304 * A056675 A062857 A061799

Adjacent sequences:  A053143 A053144 A053145 * A053147 A053148 A053149

KEYWORD

more,nonn

AUTHOR

Labos Elemer, Feb 28 2000

EXTENSIONS

a(13)-a(44) from Donovan Johnson, May 13 2010

STATUS

approved

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Last modified November 15 11:18 EST 2019. Contains 329144 sequences. (Running on oeis4.)