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A187043 Number of factors in expansion of infinitary perfect numbers (A007357) over distinct terms of A050376 1
2, 3, 3, 5, 6, 7, 7, 7, 8, 9, 8, 9, 9, 10, 10, 11, 11, 12, 13, 12, 13, 14, 14, 15, 16, 17, 18, 19, 19, 19, 20, 21, 21, 23, 22, 23 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms beyond a(17) should be regarded conjectural, because they reach beyond the known terms in A007357. - R. J. Mathar, Mar 30 2011

LINKS

Table of n, a(n) for n=1..36.

FORMULA

a(n) = A064547(A007357(n)). - R. J. Mathar, Mar 30 2011

EXAMPLE

Consider A007357(3)=90. It is a unique product 2*5*9 of distinct terms of A050376. Thus a(3)=3.

CROSSREFS

Cf. A050376, A007357

Sequence in context: A115350 A320034 A262882 * A081211 A081213 A081210

Adjacent sequences:  A187040 A187041 A187042 * A187044 A187045 A187046

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Mar 02 2011

STATUS

approved

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Last modified November 28 07:52 EST 2021. Contains 349401 sequences. (Running on oeis4.)