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A182482
6*n*A182481(n)-1.
4
5, 11, 17, 71, 29, 71, 41, 191, 107, 59, 197, 71, 311, 419, 179, 191, 101, 107, 227, 239, 881, 659, 137, 431, 149, 311, 809, 2687, 347, 179, 1301, 191, 197, 1019, 419, 431, 1997, 227, 1871, 239, 1229, 2267, 1031, 1319, 269, 827, 281, 1151, 881, 599
OFFSET
1,1
COMMENTS
By the construction of A182481, every term is lesser of twin primes.
Every lesser more than 3 of twin primes appears in the sequence.
Number m=(a(n)+1)/6 is the place of the last appearance of a(n); m is multiple of all previous places of the appearance of a(n), if they exist.
In particular, a(n) appears only once, if (a(n)+1)/6 is 1 or prime (in this case n is 1 or prime and A182481(n)=1). Conversely is not true. For example, a(10)=59 appears only once, although 10 is not prime.
LINKS
EXAMPLE
All places where 71 appears are 4,6,12. "Thus" 12 is multiple of 4 and 6.
Since (101+1)/6=17 is prime, then 101 appears only once.
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, May 01 2012
STATUS
approved