login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A252892 Primes p such that sigma(p) = 1 + p is a partition number (sorted increasingly). 0

%I #19 Jan 14 2015 12:59:39

%S 2,29,41,6841,37337,53173,105557,124753,614153,26543659,541946239,

%T 2841940499,3519222691,30388671977,6622987708039,3925922161489421,

%U 1089657644424399781,9147679068859117601,13196258966925435701,505499305314204629557,2715220650772245313219

%N Primes p such that sigma(p) = 1 + p is a partition number (sorted increasingly).

%C Primes of the form p(k) - 1, where p(k) is a partition number (see A000040).

%C Primes in A000065. Intersection of A000040 and A000065.

%C Primes in A252891. Intersection of A000040 and A252891.

%e 41 is in the sequence because 41 is prime and the sum of divisors of 41 is 1 + 41 = 42 and 42 is the partition number of 10.

%o (PARI) lista() = {v = readvec("b000041.txt"); for (n=1, #v, if (isprime(p=v[n]-1), print1(p, ", ")););} \\ _Michel Marcus_, Dec 29 2014

%Y Cf. A000040, A000041, A000065, A000203, A052001, A252891.

%K nonn

%O 1,1

%A _Omar E. Pol_, Dec 24 2014

%E More terms from _Michel Marcus_, Dec 28 2014

%E Edited. - _Wolfdieter Lang_, Jan 14 2015

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 17 22:02 EDT 2024. Contains 371767 sequences. (Running on oeis4.)