This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A049092 Primes p such that p-1 is not squarefree. 5
 5, 13, 17, 19, 29, 37, 41, 53, 61, 73, 89, 97, 101, 109, 113, 127, 137, 149, 151, 157, 163, 173, 181, 193, 197, 199, 229, 233, 241, 251, 257, 269, 271, 277, 281, 293, 307, 313, 317, 337, 349, 353, 373, 379, 389, 397, 401, 409, 421, 433, 449, 457, 461, 487 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Primes p with mu(p-1)=0, where mu is the MÃ¶bius function. - T. D. Noe, Nov 03 2003 Primes p such that the sum of the primitive roots of p (see A088144) is 0 mod p. - Jon Wharf, Mar 12 2015 LINKS T. D. Noe, Table of n, a(n) for n=1..1000 Eric Weisstein's World of Mathematics, Moebius Function EXAMPLE p=257 is here because p-1 = 256 = 2^8; p=997 is here because p-1 = 996 = 3*(2^2)*83. MATHEMATICA Select[Prime[Range[400]], MoebiusMu[ #-1]==0&] PROG (MAGMA) [ p: p in PrimesUpTo(500) | not IsSquarefree(p-1) ]; // Vincenzo Librandi, Mar 12 2015 (PARI) forprime(p=2, 500, if(!issquarefree(p-1), print(p))) \\ Michael B. Porter, Mar 16 2015 CROSSREFS Cf. A078330 (primes p with mu(p-1)=-1), A088179 (primes p such that mu(p-1)=1), A089451 (mu(p-1) for prime p). Sequence in context: A282747 A088908 A092218 * A103666 A082700 A212287 Adjacent sequences:  A049089 A049090 A049091 * A049093 A049094 A049095 KEYWORD nonn AUTHOR STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.