The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A258430 Primes in A088580. 3
 2, 5, 7, 13, 19, 13, 29, 19, 43, 37, 61, 43, 41, 31, 73, 61, 43, 97, 79, 73, 73, 73, 61, 97, 127, 97, 73, 97, 127, 109, 181, 113, 157, 103, 211, 193, 163, 109, 281, 241, 211, 181, 157, 313, 337, 241, 271, 139, 337, 193, 181, 223, 229, 151, 373, 193, 241, 379 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS These primes are neither sorted nor uniqued. They are listed in the order found in A088580. LINKS Robert Price, Table of n, a(n) for n = 1..2967 FORMULA a(n) = A088580(A065512(n)). - Michel Marcus, Jun 04 2015 MAPLE with(numtheory): A258430:=n->`if`(isprime(1+sigma(n)), 1+sigma(n), NULL): seq(A258430(n), n=1..300); # Wesley Ivan Hurt, Jul 09 2015 MATHEMATICA Select[Table[1 + DivisorSigma[1, n], {n, 10000}], PrimeQ] PROG (MAGMA) [a: n in [1..300] | IsPrime(a) where a is 1 + SumOfDivisors(n)]; // Vincenzo Librandi, May 30 2015 (PARI) select(x->isprime(x), vector(200, n, 1+sigma(n))) \\ Michel Marcus, Jun 04 2015 CROSSREFS Cf. A088580, A065512. Sequence in context: A160676 A169690 A144300 * A333242 A045353 A038985 Adjacent sequences:  A258427 A258428 A258429 * A258431 A258432 A258433 KEYWORD nonn AUTHOR Robert Price, May 29 2015 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 6 16:27 EDT 2021. Contains 343586 sequences. (Running on oeis4.)