A324895 Largest proper divisor of A276086(n); a(0) = 1.

1, 1, 1, 3, 3, 9, 1, 5, 5, 15, 15, 45, 5, 25, 25, 75, 75, 225, 25, 125, 125, 375, 375, 1125, 125, 625, 625, 1875, 1875, 5625, 1, 7, 7, 21, 21, 63, 7, 35, 35, 105, 105, 315, 35, 175, 175, 525, 525, 1575, 175, 875, 875, 2625, 2625, 7875, 875, 4375, 4375, 13125, 13125, 39375, 7, 49, 49, 147, 147, 441, 49, 245, 245, 735, 735, 2205, 245, 1225, 1225

Offset: 0

Author

Antti Karttunen, Mar 30 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 0..30030
• Index entries for sequences related to primorial base
• Index entries for sequences related to primorial numbers

Crossrefs

Cf. A002110, A032742, A053669, A276151, A276085, A276086, A324896.

Programs

PARI

A032742(n) = if(1==n,n,n/vecmin(factor(n)[,1]));
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; };
A324895(n) = A032742(A276086(n));

Formula

a(n) = A032742(A276086(n)).

For n >= 0, a(A002110(n)) = 1.

For n >= 1, a(n) = A276086(n) / A053669(n) = A276086(A276151(n)).

For n >= 1, A276085(a(n)) = A276151(n).

For n >= 1, a(A108951(n)) = A324896(n).