A008866 Prime(A052928(n+1)) + (-1)^n* prime(A109613(n)).

1, 8, 2, 18, 2, 30, 2, 42, 6, 60, 6, 78, 2, 90, 6, 112, 2, 128, 4, 144, 6, 162, 6, 186, 4, 204, 4, 216, 4, 240, 4, 268, 2, 288, 2, 308, 6, 330, 6, 352, 2, 372, 2, 390, 2, 410, 12, 450, 2, 462, 6, 480, 10, 508, 6, 532

Offset: 1

Author

N. J. A. Sloane, R. K. Guy

Keywords

• nonn

References

• Problem #1210, Series Formation, by Charles W. Trigg, J. Rec. Math., 15 (1982), 221-222.

Programs

Maple

ithprime(2*ceil(n/2))+(-1)^n*ithprime(2*floor(n/2)+1);