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Revision History for A180086 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A180086

Sum of previous terms divided by their distance from n
(history; published version)

#2 by Russ Cox at Sat Mar 31 10:25:22 EDT 2012

AUTHOR

_Dominick Cancilla (dcancilla1(AT)gmail.com), _, Aug 09 2010

Discussion

Sat Mar 31

10:25

OEIS Server: https://oeis.org/edit/global/444

#1 by N. J. A. Sloane at Fri Aug 27 03:00:00 EDT 2010

NAME

Sum of previous terms divided by their distance from n

DATA

1, 3, 6, 11, 20, 33, 54, 87, 142, 226, 360, 571, 907, 1438, 2278, 3606, 5708, 9032, 14293, 22614, 35778, 56604, 89550, 141670, 224122, 354560, 560907, 887348, 1403768, 2220731, 3513149, 5557726, 8792197, 13909055, 22003808

OFFSET

2,2

FORMULA

a(n) = n + floor(a(n-1)/1) + floor(a(n-2)/2) + ... + floor(a(1)/(n-1))

EXAMPLE

a(1)=1 by definition

a(4)=4+a(3)/1+a(2)/2+a(1)/3=4+floor(6/1)+floor(3/2)+floor(1/3)=11

KEYWORD

nonn,new

AUTHOR

Dominick Cancilla (dcancilla1(AT)gmail.com), Aug 09 2010

STATUS

approved