OFFSET
1,1
COMMENTS
A conjecture of Schinzel, if true, would imply that such a p always exists.
LINKS
T. D. Noe, Table of n, a(n) for n = 1..10000
Matthew M. Conroy, A sequence related to a conjecture of Schinzel, J. Integ. Seqs. Vol. 4 (2001), #01.1.7.
Peter Luschny, Schinzel-Sierpinski conjecture and Calkin-Wilf tree.
A. Schinzel and W. Sierpiński, Sur certaines hypothèses concernant les nombres premiers, Acta Arithmetica 4 (1958), 185-208; erratum 5 (1958) p. 259.
FORMULA
a(n) = (A060324(n) + 1) * n - 1. - Reinhard Zumkeller, Aug 28 2014
EXAMPLE
1 = (2+1)/(2+1), 2 = (5+1)/(2+1), 3 = (11+1)/(3+1), 4 = (11+1)/(2+1), ...
MAPLE
a:= proc(n) local q;
q:= 2;
while not isprime(n*(q+1)-1) do
q:= nextprime(q);
od; n*(q+1)-1
end:
seq(a(n), n=1..300);
MATHEMATICA
a[n_] := (q = 2; While[ ! PrimeQ[n*(q+1)-1], q = NextPrime[q]]; n*(q+1)-1); Table[a[n], {n, 1, 57}] (* Jean-François Alcover, Feb 17 2012, after Maple *)
PROG
(Haskell)
a062251 n = (a060324 n + 1) * n - 1 -- Reinhard Zumkeller, Aug 28 2014
CROSSREFS
KEYWORD
nonn,nice,easy
AUTHOR
N. J. A. Sloane, Jul 01 2001
EXTENSIONS
More terms from Vladeta Jovovic, Jul 02 2001
STATUS
approved