

A075694


a(1)=1, then "jump over next prime": a(n) = 2 nextprime(a(n1))a(n1).


3



1, 3, 7, 15, 19, 27, 31, 43, 51, 55, 63, 71, 75, 83, 95, 99, 103, 111, 115, 139, 159, 167, 179, 183, 199, 223, 231, 235, 243, 259, 267, 271, 283, 303, 311, 315, 319, 343, 351, 355, 363, 371, 375, 383, 395, 399, 403, 415, 423, 439, 447, 451, 463, 471, 487, 495
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OFFSET

1,2


COMMENTS

The rule "jump over next smth" can be varied. In the A075695 the example: "jump over next second prime" is given.


LINKS

Table of n, a(n) for n=1..56.


FORMULA

a(1)=1, a(n) = 2 nextprime(a(n1))a(n1).


EXAMPLE

a(1)=1; next prime (smallest larger than a(1))=2; "jump over" it: 2+(21)=3; a(2)=3; next prime (smallest larger than a(2))=5; "jump over" it: 5+(53)=7; a(7)=31; next prime (smallest larger than a(7))=37; "jump over" it: 37+(3731)=43.


MAPLE

a(1) := 1; a(n)=2*nextprime(a(n1))a(n1);


CROSSREFS

Cf. A075695.
Sequence in context: A089432 A111294 A092899 * A186300 A144751 A138847
Adjacent sequences: A075691 A075692 A075693 * A075695 A075696 A075697


KEYWORD

easy,nonn


AUTHOR

Zak Seidov, Sep 26 2002


STATUS

approved



