This site is supported by donations to The OEIS Foundation.

 Annual Appeal: Please make a donation to keep the OEIS running. In 2018 we replaced the server with a faster one, added 20000 new sequences, and reached 7000 citations (often saying "discovered thanks to the OEIS"). Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A163083 Primes of the form n\$ + 1 which are the greater of twin primes. Here '\$' denotes the swinging factorial function (A056040). 2
 7, 31, 51481, 1580132580471901 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A163075 and of A006512. LINKS Peter Luschny, Swinging Primes. MAPLE a := proc(n) select(s->isprime(s) and isprime(s-2), map(k -> A056040(k)+1, [\$4..n])) end: MATHEMATICA sf[n_] := With[{f = Floor[n/2]}, Pochhammer[f+1, n-f]/f!]; Do[ If[ PrimeQ[p = sf[n] + 1] && PrimeQ[p - 2], Print["n = ", n, " p = ", p]], {n, 1, 400}] (* Jean-François Alcover, Jul 29 2013 *) CROSSREFS Cf. A163075, A006512. Sequence in context: A134709 A139314 A290969 * A101329 A193637 A214490 Adjacent sequences:  A163080 A163081 A163082 * A163084 A163085 A163086 KEYWORD nonn AUTHOR Peter Luschny, Jul 21 2009 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 December 13 17:32 EST 2018. Contains 318086 sequences. (Running on oeis4.)