A082865 a(n) is the sum of the preceding terms that are coprime to n.

1, 2, 3, 4, 10, 1, 21, 26, 44, 26, 94, 2, 182, 5, 382, 31, 834, 38, 1668, 57, 666, 119, 4216, 157, 8574, 395, 5735, 6385, 29678, 309, 49683, 62902, 80713, 143496, 320705, 414247, 1125010, 878510, 2929386, 545342, 6609659, 507670, 7117329, 14284850

Offset

1,2

Links

Ivan Neretin, Table of n, a(n) for n = 1..1000

Example

a(6)=1 as 2,3,4 and 10 all have gcd(6,x)>1.

Mathematica

a = {1, 2}; Do[AppendTo[a, Total@Select[a, GCD[n, #] == 1 &]], {n, 3, 44}]; a (* Ivan Neretin, Apr 27 2017 *)

Prog

(PARI) { v=vector(100, i, 0); v[1]=1; v[2]=2; print1("1, 2, "); for (i=3, 100, for (j=1, i-1, if (gcd(i, v[j]) == 1, v[i]+=v[j])); print1(v[i]", ")) }

Crossrefs

Sequence in context: A245366 A135112 A286709 * A359996 A368222 A265348

Adjacent sequences: A082862 A082863 A082864 * A082866 A082867 A082868

Keyword

nonn

Author

Jon Perry, May 24 2003

Status

approved