

A179383


a(n) = 2*k(n)1 where k(n) is the sequence of positions of records in A179382.


7



1, 5, 9, 11, 13, 19, 25, 29, 37, 53, 59, 61, 67, 83, 101, 107, 121, 131, 139, 149, 163, 173, 179, 181, 197, 211, 227, 269, 293, 317, 347, 349, 373, 379, 389, 419, 421, 443, 461, 467, 491, 509, 523, 541, 547, 557, 563, 587, 613, 619, 653, 659, 661, 677, 701, 709, 757
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OFFSET

1,2


COMMENTS

Records in A179382(k(n)) = 1, 2, 3, 5, 6, 9, 10, 14, 18, 26, 29, ....
are located at k(n) = 1, 3, 5, 6, 7, 10, 13, 15, 19, 27, 30, 31,..
The current sequence is a simple transformation of this k(n) sequence.
Question: Are there any terms in the sequence with two or more distinct prime divisors?
Some very plausible conjectures: 1) The sequence consists of primes and squares of primes; 2) The set of squares is finite; 3) A prime p>=5 is in the sequence iff it has primitive root 2 (A001122) ; 4) There exists l such that, for n>l, A179383(n) =A139099(n+l) . [From Vladimir Shevelev , Jul 14 2010]


LINKS

Peter J. C. Moses, Table of n, a(n) for n = 1..8500


CROSSREFS

Cf. A139099, A167791, A002326, A179382
Sequence in context: A078621 A287521 A287529 * A076195 A191924 A128310
Adjacent sequences: A179380 A179381 A179382 * A179384 A179385 A179386


KEYWORD

nonn


AUTHOR

Vladimir Shevelev, Jul 12 2010


EXTENSIONS

Definition rephrased and sequence extended by R. J. Mathar, Jul 13 2010
I made a change to Conjecture 4).  Vladimir Shevelev, Jul 18 2010


STATUS

approved



