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A324895
Largest proper divisor of A276086(n); a(0) = 1.
9
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
0,4
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).
PROG
(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; };
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 30 2019
STATUS
approved