A175510 (2*n)-th twin prime minus 2*(n-th twin prime).

-1, 1, 3, 7, 15, 25, 33, 43, 45, 55, 63, 61, 69, 55, 81, 37, 63, 67, 93, 73, 141, 133, 159, 163, 207, 217, 231, 247, 261, 355, 363, 349, 375, 343, 477, 469, 483, 439, 465, 457, 531, 439, 447, 439, 453, 505, 525, 439, 441, 469, 477, 469

Offset: 1

Author

Juri-Stepan Gerasimov, Jun 02 2010

Keywords

• sign

Examples

			a(1)=-1 because A001097(2*1)-2*A001097(1)=5-2*3=-1.
		

Crossrefs

Cf. A066066.

Formula

a(n)=A001097(2n)-2*A001097(n).