A192688 Sum of omega-values for two consecutive indices where they equal the omega-value at the sum of the two indices.

1, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 4, 3, 3

Offset

1,2

Comments

The sequence contains sums A001221(n) + A001221(n+1) whenever they are equal to A001221(2n+1).

Generated by indices n = 1, 7, 16, 31, 52, 82, 97, 136, 157, 172, 178, 192, 199, 232, 241, 256, 262, 277, 292, ...

Links

Table of n, a(n) for n=1..87.

Maple

for n from 1 to 2000 do
        if A001221(n)+A001221(n+1) = A001221(2*n+1) then
                printf("%d, ", A001221(2*n+1)) ;
        end if;
end do: # R. J. Mathar, Oct 12 2011

Mathematica

f[n_] := Block[{a = PrimeNu[n] + PrimeNu[n + 1]}, If[a == PrimeNu[2n + 1], Return@ a]]; k = 1; lst = {}; While[k < 2600, If[f@k > 0, AppendTo[lst, f@ k]]; k++]; lst (* Robert G. Wilson v, Aug 29 2011 *)

Crossrefs

Cf. A001221, A059957, A092523.

Sequence in context: A127971 A319290 A230516 * A156752 A345073 A086673

Adjacent sequences: A192685 A192686 A192687 * A192689 A192690 A192691

Keyword

nonn

Author

Juri-Stepan Gerasimov, Jul 07 2011

Status

approved