

A204904


p(n)q(n), where (p(n), q(n)) is the least pair of odd primes for which n divides p(n)q(n).


1



2, 2, 6, 4, 10, 6, 14, 8, 18, 10, 22, 12, 26, 14, 30, 16, 34, 18, 38, 20, 42, 22, 46, 24, 50, 26, 54, 28, 58, 30, 62, 32, 66, 34, 70, 36, 74, 38, 78, 40, 82, 42, 86, 44, 90, 46, 94, 48, 98, 50, 102, 52, 106, 54, 110, 56, 114, 58, 118, 60, 122, 62, 126, 64, 130
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OFFSET

1,1


COMMENTS

This sequence agrees with A109043 for 0<n<=65; what about all larger n?
For a guide to related sequences, see A204892.
Sequence agrees with A109043 at least up to 6400.  Michel Marcus, Mar 14 2018
If Polignac's conjecture is true, then this is a duplicate of A109043.  Robert Israel, Mar 14 2018


LINKS

Table of n, a(n) for n=1..65.
Wikipedia, Polignac's conjecture


EXAMPLE

1 = (53)/2=(73)/4=(133)/6=(113)/8=...
2 = (53)/1=(115)/3=(73)/5=(173)/7=...


MATHEMATICA

(See the program at A204900.)


PROG

(PARI) a(n) = {forprime(p=5, , forprime(q=3, p1, d = pq; if ((d % n) == 0, return (d)); ); ); } \\ Michel Marcus, Mar 14 2018


CROSSREFS

Cf. A066043, A109043, A204900, A204892, A210530.
Sequence in context: A053213 A292258 A140524 * A109043 A054585 A278236
Adjacent sequences: A204901 A204902 A204903 * A204905 A204906 A204907


KEYWORD

nonn


AUTHOR

Clark Kimberling, Jan 20 2012


STATUS

approved



