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A273353 Number of divisors of A067128(n). 1
1, 2, 2, 3, 4, 4, 4, 6, 6, 6, 8, 8, 9, 10, 12, 12, 12, 12, 12, 12, 16, 16, 18, 20, 20, 24, 24, 24, 24, 24, 24, 24, 24, 24, 30, 32, 32, 36, 36, 40, 40, 48, 48, 48, 48, 48, 48, 48, 48, 60, 64, 64, 72, 72, 72, 80, 80, 84, 90, 96, 96, 96, 96, 96, 96, 96, 96, 96, 100, 108, 120, 120, 120, 128, 128, 144, 144, 144, 144, 144, 160 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Is a(n + 1) / a(n) ~ 1 for large n?

Every term in this sequence also appears in A002183, where every element of this sequence occurs exactly once.

In A067128 it is asked if A034287 = A067128. If that is the case then this sequence is also the number of divisors of A034287.

LINKS

Table of n, a(n) for n=1..81.

FORMULA

a(n) = A000005(A067128(n)).

PROG

(PARI) is_a067128(n) = my(nd=numdiv(n)); for(k=1, n-1, if(numdiv(k) > nd, return(0))); return(1)

for(n=1, 50, if(is_a067128(n), print1(numdiv(n), ", "))) \\ Felix Fröhlich, May 24 2016

CROSSREFS

Cf. A000005, A002182, A002183, A034287, A067128.

Sequence in context: A262976 A224709 A070172 * A259197 A130128 A210556

Adjacent sequences:  A273350 A273351 A273352 * A273354 A273355 A273356

KEYWORD

nonn

AUTHOR

David A. Corneth, May 20 2016

STATUS

approved

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Last modified April 18 10:44 EDT 2019. Contains 322209 sequences. (Running on oeis4.)