A117533 - OEIS

%I #18 Mar 11 2021 17:01:36

%S 1,3,7,13,16,23,31,41,46,57,69,83,92,107,124,137,155,175,191,213,232,

%T 255,279,305,326,353,382,407,437,469,497,531,562,597,633,671,704,743,

%U 784,821,863,907,947,993,1036,1083,1131,1181,1226,1277,1330,1379,1433

%N a(n) = Sum_{k=1..n} A117532(k).

%C a(n) is coprime to n.

%H Michael De Vlieger, <a href="/A117533/b117533.txt">Table of n, a(n) for n = 1..3000</a>

%p A117532 := proc(nmax) local a,n,nxt, asu ; a := [1] ; asu := 1 ; while nops(a) < nmax do n := nops(a)+1 ; nxt := 1 ; while nxt in a or gcd(n, asu+nxt) <> 1 do nxt := nxt+1 ; od ; a := [op(a),nxt] ; asu := asu+nxt ; od ; a ; end: A117533 := proc(a117532,n) local i ; add(op(i,a117532),i=1..n) ; end: a117532 := A117532(80) : seq( A117533(a117532,n),n=1..nops(a117532)) ; # _R. J. Mathar_, May 10 2007

%t Accumulate@ Fold[Append[#1, Block[{k = 2}, While[Nand[FreeQ[#1, k], CoprimeQ[Total@ #1 + k, #2]], k++]; k]] &, {1}, Range[2, 53]] (* _Michael De Vlieger_, Sep 30 2017 *)

%Y Cf. A117532, A117534.

%K nonn

%O 1,2

%A _Leroy Quet_, Mar 26 2006

%E More terms from _R. J. Mathar_, May 10 2007