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A093152 Number of odd composites below 10^n that are congruent to 3 modulo 4. 2
0, 12, 163, 1881, 20192, 210678, 2167602, 22119050, 224575958, 2272470765, 22940965468, 231196012323, 2326967172345, 23397529032871, 235077714312816, 2360380827753871, 23688221418030854, 237630022854838725, 2382971166321456083, 23889590198589663868 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..20.

FORMULA

For n>1, a(n) = 25*10^(n-2) - A091099(n) [From Max Alekseyev, May 17 2009]

EXAMPLE

Below 10^2 there are 12 odd composites 3 mod 4 so a(2)=12

CROSSREFS

Cf. A093151 A093153 A091295 A091098 A091099.

Sequence in context: A307071 A138455 A024221 * A282010 A143583 A231541

Adjacent sequences:  A093149 A093150 A093151 * A093153 A093154 A093155

KEYWORD

nonn

AUTHOR

Enoch Haga, Mar 24 2004

EXTENSIONS

a(9) from Ryan Propper, Jun 21 2005

a(10)-a(20) from Max Alekseyev, May 17 2009, Oct 08 2013

STATUS

approved

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Last modified August 5 20:11 EDT 2021. Contains 346488 sequences. (Running on oeis4.)