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 A127076 a(0)=1. a(n) = a(n-1) + (sum of the earlier terms {among terms a(0) through a(n-1)} which are coprime to n). 2
 1, 2, 3, 6, 10, 22, 23, 90, 117, 175, 319, 746, 1264, 3925, 8313, 10690, 23566, 64525, 133493, 380783, 903835, 2427039, 6349271, 16657466, 24493816, 74970066, 84860988, 133884920, 144156567, 630996725, 637860615, 2396049996, 3819335725 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS Robert Israel, Table of n, a(n) for n = 0..3125 EXAMPLE The terms of the sequence, among terms a(0) through a(7), which are coprime to 8 are a(0)=1, a(2)=3 and a(6) = 23. So a(8) = a(7) +1 +3 +23 = 117. MAPLE R:= [1]: for n from 1 to 100 do x:= R[-1] + convert(select(t -> igcd(t, n)=1, R), `+`); R:= [op(R), x]; od: R; # Robert Israel, Sep 15 2020 MATHEMATICA f[l_List] := Append[l, l[[ -1]] + Plus @@ Select[l, GCD[ #, Length[l]] == 1 &]]; Nest[f, {1}, 32] (* Ray Chandler, Jan 06 2007 *) CROSSREFS Cf. A127075. Sequence in context: A036650 A049889 A014270 * A137208 A049527 A074371 Adjacent sequences: A127073 A127074 A127075 * A127077 A127078 A127079 KEYWORD nonn AUTHOR Leroy Quet, Jan 04 2007 EXTENSIONS Extended by Ray Chandler, Jan 06 2007 STATUS approved

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Last modified May 28 18:29 EDT 2023. Contains 363019 sequences. (Running on oeis4.)