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A112642
Primorial number quotients arising in A007684: a(n) = A002110(A007684(n))/A002110(n-1).
1
6, 15015, 33426748355, 1357656019974967471687377449, 7105630242567996762185122555313528897845637444413640621, 1924344668948998025181489521338230544342953524990122861050411878226909135705454891961917517
OFFSET
1,1
COMMENTS
These numbers are (perhaps the smallest) squarefree solutions to Puzzle 329 of Rivera; a(n) is abundant, not divisible by the first n-1 prime numbers, i.e., the least prime divisor of a(n) is the n-th prime number.
Duplicate of A007702.
LINKS
Carlos Rivera, Puzzle 329. Odd abundant numbers not divided by 2 or 3, The Prime Puzzles and Problems Connection.
FORMULA
a(n) = A002110(A007684(n))/A002110(n-1).
EXAMPLE
The corresponding sigma(a(n))/a(n) abundance ratios are as follows: 2, 2.14825, 2.00097, 2.01433, 2.00587, 2.00101, ...;
the terms have 2,3,5,7,11,... as least prime divisors.
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Sep 19 2005
EXTENSIONS
Term a(2) and name corrected by Andrey Zabolotskiy, Jul 16 2022
STATUS
approved