A119746 Sum of previous term and preceding relatively prime terms.

1, 2, 3, 6, 7, 19, 38, 49, 118, 197, 440, 716, 992, 1268, 1544, 1820, 2040, 2313, 9524, 12113, 33210, 45596, 60298, 74944, 89646, 102032, 116678, 129067, 684624, 826077, 1219334, 2189180, 2203807, 7807703, 15615406, 18789059, 50019871, 100039302

Offset: 1

Author

Franklin T. Adams-Watters, Jun 16 2006

Keywords

• nonn

Crossrefs

Cf. A120610.

Programs

Mathematica

s={1,2};Do[AppendTo[s,s[[-1]]+Total[Select[s,CoprimeQ[#,s[[-1]]]&]]],{n,36}];s (* James C. McMahon, Feb 24 2025 *)

Formula

a(1)=1, a(2)=2, for n>=2, a(n+1) = a(n) + Sum_{1<=k

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