A049635 a(n) = T(n,n+3), array T as in A049627.

2, 7, 11, 16, 23, 32, 39, 50, 63, 74, 89, 106, 117, 138, 159, 174, 199, 224, 241, 270, 299, 320, 349, 384, 409, 442, 481, 508, 549, 594, 621, 668, 707, 740, 791, 834, 869, 922, 979, 1016, 1073, 1134, 1169, 1234, 1299, 1340, 1403, 1470, 1517, 1584, 1655, 1706

Offset: 0

Author

Clark Kimberling

Keywords

• nonn

Crossrefs

Cf. A049627.

Programs

PARI

T(n,k) = (n+1)*(k+1) - sum(i=0, n, sum(j=0, k, gcd(i,j)>1)); \\ A049627
a(n) = T(n, n+3); \\ Michel Marcus, Aug 06 2021

Extensions

More terms from Sean A. Irvine, Aug 05 2021