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A324889 a(1) = 1, and for n > 1, a(n) = A276086(n) * a(A064989(n)). 2
1, 3, 18, 9, 324, 15, 3240, 15, 270, 810, 291600, 75, 14580000, 24300, 2250, 225, 6561000000, 1125, 1640250000000, 6750, 607500, 3645000, 3690562500000000, 1875, 337500, 546750000, 56250, 1822500, 41518828125000000000, 105, 581263593750000000000, 21, 1020600, 918540000, 283500, 315, 40688451562500000000000, 688905000000, 765450000, 5670 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..210

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to primorial base

Index entries for sequences related to primorial numbers

FORMULA

a(1) = 1, and for n > 1, a(n) = A276086(n) * a(A064989(n)).

A001222(a(n)) = A324890(n).

For all n >= 0, a(A002110(n)) = A002110(1+n)/2.

PROG

(PARI)

A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};

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; };

A324889(n) = if(1==n, n, A276086(n) * A324889(A064989(n)));

CROSSREFS

Cf. A002110, A064989, A276086, A324890.

Sequence in context: A131635 A324554 A007475 * A281791 A281722 A098874

Adjacent sequences:  A324886 A324887 A324888 * A324890 A324891 A324892

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 30 2019

STATUS

approved

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Last modified November 15 06:23 EST 2019. Contains 329144 sequences. (Running on oeis4.)