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A324651 Bisection of A324650: a(n) = A000010(A276086(2*n)). 3
1, 2, 6, 4, 8, 24, 20, 40, 120, 100, 200, 600, 500, 1000, 3000, 6, 12, 36, 24, 48, 144, 120, 240, 720, 600, 1200, 3600, 3000, 6000, 18000, 42, 84, 252, 168, 336, 1008, 840, 1680, 5040, 4200, 8400, 25200, 21000, 42000, 126000, 294, 588, 1764, 1176, 2352, 7056, 5880, 11760, 35280, 29400, 58800, 176400, 147000, 294000, 882000, 2058 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..15015

Index entries for sequences related to primorial base

Index entries for sequences related to primorial numbers

FORMULA

a(n) = A324650(2*n) = A000010(A276086(2*n)).

PROG

(PARI)

A324650(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m *= (prime(i)-1)*(prime(i)^(((n%nextpr)/pr)-1)); n-=(n%nextpr)); pr=nextpr); (m); };

A324651(n) = A324650(n+n);

(PARI)

A276086(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m*=(prime(i)^((n%nextpr)/pr)); n-=(n%nextpr)); pr=nextpr); m; };

A324651(n) = eulerphi(A276086(n+n));

CROSSREFS

Cf. A000010, A276086, A324650.

Sequence in context: A259284 A204906 A097265 * A342808 A201895 A192408

Adjacent sequences:  A324648 A324649 A324650 * A324652 A324653 A324654

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 10 2019

STATUS

approved

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Last modified June 21 10:02 EDT 2021. Contains 345358 sequences. (Running on oeis4.)