A049620 a(n) = T(n,n), array T as in A049615.

0, 0, 3, 6, 11, 14, 23, 26, 35, 42, 55, 58, 75, 78, 95, 110, 127, 130, 155, 158, 183, 202, 227, 230, 263, 274, 303, 322, 355, 358, 403, 406, 439, 466, 503, 526, 575, 578, 619, 650, 699, 702, 763, 766, 815, 858, 907, 910, 975, 990, 1051, 1090, 1147, 1150, 1223, 1254, 1319, 1362, 1423, 1426, 1515, 1518, 1583

Offset

0,3

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Mathematica

T[n_, k_]:= Length[Select[Flatten[Table[{x, y}, {x, 0, n}, {y, 0, k}], 1], GCD @@ # > 1 &]]; Table[T[n, n], {n, 0, 65}] (* G. C. Greubel, Dec 16 2019 *)

Crossrefs

Cf. A049615, A049616, A049617, A049618, A049619, A049621, A049622, A049623.

Sequence in context: A122599 A342954 A015823 * A350438 A329741 A310096

Adjacent sequences: A049617 A049618 A049619 * A049621 A049622 A049623

Keyword

nonn

Author

Clark Kimberling

Extensions

Terms a(38) onward added by G. C. Greubel, Dec 16 2019

Status

approved