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A136022 First differences of A136021. 1
19, 1028, 63326, 4417267, 336418691, 27095099730, 2264740360646, 194526458511192, 17050085068702458, 1517704371492095702, 136758640772944755122, 12445444666179480674989, 1141852084948606732236114, 105483948921834512942168239 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..14.

FORMULA

a(n) = A136021(n)-A136021(n-1).

EXAMPLE

a(1)=19 because at 10^0 the prime divisor sum in A136021 is zero, so 19-0=19. From the second sum in A136021, 1047, subtract 19, so that a(2) = 1028.

CROSSREFS

Cf. A136021.

Sequence in context: A192569 A238740 A285862 * A203582 A136021 A195214

Adjacent sequences:  A136019 A136020 A136021 * A136023 A136024 A136025

KEYWORD

more,nonn

AUTHOR

Enoch Haga, Dec 10 2007, Dec 12 2007

EXTENSIONS

a(6) from R. J. Mathar, Dec 12 2007

Edited by R. J. Mathar, Apr 17 2009

a(7)-a(11) from Max Alekseyev, Jan 30 2012

a(12)-a(14) from Hiroaki Yamanouchi, Jun 29 2014

STATUS

approved

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Last modified April 20 01:55 EDT 2021. Contains 343118 sequences. (Running on oeis4.)