Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A065512
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A065512 Numbers n such that sigma(n) + 1 is prime. +0
1
1, 3, 5, 6, 10, 11, 12, 17, 20, 22, 24, 26, 27, 29, 30, 38, 41, 42, 45, 46, 51, 55, 59, 62, 68, 69, 71, 77, 82, 85, 88, 91, 99, 101, 104, 105, 106, 107, 108, 114, 116, 118, 125, 126, 132, 135, 136, 137, 140, 141, 145, 146, 147, 149, 150, 155, 158, 160, 161 (list; graph; listen)
OFFSET

1,2

EXAMPLE

sigma(10) + 1 = 18 + 1 = 19 (prime). sigma(24) + 1 = 60 + 1 = 61 (prime).

MATHEMATICA

Select[ Range[170], PrimeQ[ DivisorSigma[1, # ] + 1] & ]

CROSSREFS

Cf. A000203.

Adjacent sequences: A065509 A065510 A065511 this_sequence A065513 A065514 A065515

Sequence in context: A102606 A102372 A095829 this_sequence A066147 A140951 A065873

KEYWORD

nonn

AUTHOR

Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Nov 26 2001

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified October 13 20:18 EDT 2008. Contains 145016 sequences.


AT&T Labs Research