login
A140120
Primes of the form prime(x)*prime(x+1) - (prime(x+1)-prime(x)).
0
5, 13, 73, 433, 661, 2017, 3121, 6553, 16633, 47041, 53353, 55681, 116929, 159193, 198901, 216217, 223681, 250993, 256021, 364801, 404461, 444841, 938953, 988021, 1022113, 1299457, 1340929, 1476217, 1545001, 1640953, 1687393, 1932001, 1971181, 2030617, 2099593, 2119921, 2178541, 2301241
OFFSET
1,1
EXAMPLE
2*3 - (3-2) = 2*3 - 1 = 5;
3*5 - (5-3) = 3*5 - 2 = 13;
7*11 - (11-4) = 7*11 - 4 = 73.
MATHEMATICA
a = {}; Do[p1 = Prime[n]; p2 = Prime[n + 1]; p = p1*p2 - (p2 - p1); If[PrimeQ[p], AppendTo[a, p]], {n, 10^2}]; a
Select[#[[1]]#[[2]]-(#[[2]]-#[[1]])&/@Partition[Prime[Range[250]], 2, 1], PrimeQ] (* Harvey P. Dale, Feb 01 2011 *)
CROSSREFS
Sequence in context: A115329 A272645 A137702 * A303962 A304927 A163732
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Harvey P. Dale, Feb 01 2011
STATUS
approved