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A319865
Product of distinct prime factors of highly composite numbers (definition 1, A002182).
1
1, 2, 2, 6, 6, 6, 6, 6, 30, 30, 30, 30, 30, 30, 210, 210, 210, 210, 210, 210, 210, 210, 210, 210, 2310, 210, 210, 2310, 2310, 2310, 2310, 2310, 2310, 2310, 2310, 2310, 2310, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 30030, 510510, 30030
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Highly Composite Number
FORMULA
a(n) = A007947(A002182(n)). - Michel Marcus, Sep 30 2018
EXAMPLE
n | A002182(n) | a(n)
---+----------------------------------+--------------------------
24 | 25200 = 2^4 * 3^2 * 5^2 * 7 | 210 = 2 * 3 * 5 * 7
25 | 27720 = 2^3 * 3^2 * 5 * 7 * 11 | 2310 = 2 * 3 * 5 * 7 * 11
26 | 45360 = 2^4 * 3^4 * 5 * 7 | 210 = 2 * 3 * 5 * 7
27 | 50400 = 2^5 * 3^2 * 5^2 * 7 | 210 = 2 * 3 * 5 * 7
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 29 2018
STATUS
approved