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A076669
Primes of the form n^2*totient(n)+1 (or A053191(n) + 1).
0
2, 5, 19, 101, 73, 257, 487, 401, 577, 2029, 1801, 23549, 29401, 25601, 21169, 77659, 83233, 52489, 121001, 57601, 115321, 87121, 197137, 564899, 462401, 697049, 649801, 403369, 588061, 1020101, 887113, 893041, 922561, 696961, 1910413, 837937, 940801, 1411481
OFFSET
1,1
COMMENTS
These primes are neither sorted nor unique. They are listed in the order they are found. - Michel Marcus, Jul 23 2015
PROG
(PARI) lista(nn) = for (n=1, nn, if (isprime(p=n^2*eulerphi(n)+1), print1(p, ", "))); \\ Michel Marcus, Jul 23 2015
CROSSREFS
Cf. A053191.
Sequence in context: A007003 A020117 A054687 * A093502 A009311 A211207
KEYWORD
easy,nonn
AUTHOR
Enoch Haga, Jan 16 2004
EXTENSIONS
Name corrected by Michel Marcus, Jul 23 2015
STATUS
approved