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A082865 a(n) is the sum of the preceding terms that are coprime to n. 1
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 (list; graph; refs; listen; history; text; internal format)
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 * A265348 A158929 A255479

Adjacent sequences:  A082862 A082863 A082864 * A082866 A082867 A082868

KEYWORD

nonn

AUTHOR

Jon Perry, May 24 2003

STATUS

approved

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Last modified June 2 10:12 EDT 2020. Contains 334769 sequences. (Running on oeis4.)