A127019 Least s with s, t both semiprime and s-2n = t.

6, 10, 10, 14, 14, 21, 35, 22, 22, 26, 26, 33, 35, 34, 34, 38, 38, 46, 77, 46, 46, 58, 55, 57, 65, 58, 58, 62, 62, 69, 77, 74, 87, 74, 74, 82, 95, 82, 82, 86, 86, 93, 95, 94, 94, 106, 115, 106, 119, 106, 106, 118, 115, 118, 119, 118, 118, 122, 122, 129, 143, 133, 141, 134

Offset

1,1

Links

Table of n, a(n) for n=1..64.

Mathematica

sp=Select[Range[1000], PrimeOmega[#]==2&]; seq={}; Do[s=0; Until[t=sp[[s]]-2n; PrimeOmega[t]==2&&t>0, s++]; AppendTo[seq, sp[[s]]], {n, 64}]; seq (* James C. McMahon, Dec 30 2024 *)

Crossrefs

Cf. A127018, A020484.

Sequence in context: A071630 A334937 A003862 * A175612 A024746 A111093

Adjacent sequences: A127016 A127017 A127018 * A127020 A127021 A127022

Keyword

nonn

Author

Rick L. Shepherd, Jan 02 2007

Status

approved