A073128 - OEIS

A073128

Integer quotients arising in A063986.

0, 1, 1, 5, 5, 49, 118, 121, 2406, 2698, 4182, 4946, 153627, 3087192, 8203485, 38394376, 487844934, 2822741576, 4140154385, 4397137572, 8583966231

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OFFSET

1,4

LINKS

Table of n, a(n) for n=1..21.

FORMULA

a(n)=Sum[cototient[j], j=1..A063986(n)]/A063986(n)

EXAMPLE

n=15, A063986(15)=41846733, sum of first 41846733 cototients is s=343289046464505, a(15)=s/41846733. Only in knowledge of either the quotients or of partial sums of cototients is it possible to continue A063986 without recomputing previous terms!

CROSSREFS

Cf. A051953, A000010, A002088, A048920, A000217, A050226, A063986.

Sequence in context: A178693 A065238 A196388 * A189749 A368894 A009390

Adjacent sequences: A073125 A073126 A073127 * A073129 A073130 A073131

KEYWORD

more,nonn

AUTHOR

Labos Elemer, Jul 16 2002

EXTENSIONS

Changed A063896 to A063986 and a(16)-a(21) from Donovan Johnson, May 11 2010

STATUS

approved