A058341 Primes p such that phi(x) = p - 1 has more than 2 solutions.

3, 5, 7, 13, 17, 19, 37, 41, 43, 61, 73, 89, 97, 101, 109, 113, 157, 163, 181, 193, 233, 241, 257, 277, 281, 313, 337, 349, 353, 397, 401, 409, 421, 433, 449, 457, 461, 487, 521, 541, 577, 593, 601, 613, 617, 641, 661, 673, 701, 733, 757, 761, 769, 821, 829

Offset

1,1

Comments

There are always at least 2 such values: p and 2p. - Franklin T. Adams-Watters, May 17 2010

Links

Table of n, a(n) for n=1..55.

Example

Phi(x) = 1152 = 1153-1 has 54 solutions as follows: {1153, 1241, 1261, 1351, 1547, 1615, 1731, 1737, 1887, 1989, 2037, 2295, 2306, 2308, 2336, 2368, 2432, 2482, 2516, 2522, 2584, 2702, 2716, 2912, 2920, 2960, 3040, 3094, 3230, 3456, 3462, 3474, 3492, 3504, 3552, 3640, 3648, 3672, 3744, 3774, 3876, 3978, 4032, 4074, 4284, 4320, 4368, 4380, 4440, 4560, 4590, 4680, 5040, 5460}.

Crossrefs

Cf. A000010, A006093.

Cf. A014197, A058277, A005277. - Franklin T. Adams-Watters, May 17 2010

Sequence in context: A174265 A346645 A107360 * A116036 A304122 A032397

Adjacent sequences: A058338 A058339 A058340 * A058342 A058343 A058344

Keyword

nonn

Author

Labos Elemer, Dec 14 2000

Status

approved