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Partial sums of A007464.
2

%I #18 Jul 25 2020 10:39:10

%S 1,2,4,7,11,17,23,34,44,62,78,98,122,148,168,213,253,291,325,387,433,

%T 487,537,621,671,773,851,955,1053,1143,1213,1402,1484,1614,1698,1818,

%U 1930,2060,2180,2412,2564,2798,2930,3060,3268,3550,3690,4152,4332,4542

%N Partial sums of A007464.

%H Reinhard Zumkeller, <a href="/A178063/b178063.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = Sum_{i=0..n} A007464(i).

%p a007464:= proc(n) option remember;

%p `if`(n=0, 1, add(igcd(procname(i), procname(n-1-i)), i=0..n-1))

%p end proc:

%p ListTools[PartialSums](map(a007464,[$0..100])); # _Robert Israel_, Mar 22 2015

%t (* b is A007464 *) b[0] = 1; b[1] = 1; b[n_] := b[n] = Sum[GCD[b[k], b[n - k - 1]], {k, 0, n - 1}];

%t b /@ Range[0, 100] // Accumulate (* _Jean-François Alcover_, Jul 25 2020 *)

%o (Haskell)

%o a178063 n = a178063_list !! n

%o a178063_list = scanl1 (+) a007464_list

%o -- _Reinhard Zumkeller_, Jan 21 2014

%Y Cf. A007464.

%K nonn,easy

%O 0,2

%A _Jonathan Vos Post_, May 18 2010

%E a(45) fixed by _Reinhard Zumkeller_, Jan 21 2014