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A332902 a(1) = 1, then after the first differences of A332809.

%I A332902 #7 Apr 04 2020 21:23:58
%S A332902 1,1,1,0,1,1,1,-2,2,0,1,0,1,1,1,-5,1,3,1,-2,4,-2,1,-2,0,2,-1,2,1,1,1,
%T A332902 -9,11,-9,10,-6,1,1,1,-5,1,6,1,-5,5,-3,1,-5,7,-6,2,0,1,-1,2,-1,2,0,1,
%U A332902 0,1,1,0,-13,15,1,1,-14,16,-2,1,-10,1,1,4,-3,12,-10,1,-9,3,-1,1,7,-6,8,1,-9,1,7,4,-9,8,-6,7,-15,1,10
%N A332902 a(1) = 1, then after the first differences of A332809.
%H A332902 Antti Karttunen, <a href="/A332902/b332902.txt">Table of n, a(n) for n = 1..10200</a>
%H A332902 Antti Karttunen, <a href="/A332902/a332902.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%F A332902 a(1) = 1, and for n > 1, a(n) = A332809(n) - A332809(n-1).
%F A332902 a(p) = 1 for all primes p.
%o A332902 (PARI)
%o A332902 up_to = 105;
%o A332902 A332809list(up_to) = { my(v=vector(up_to)); v[1] = Set([1]); for(n=2,up_to, my(f=factor(n)[, 1]~, s=Set([n])); for(i=1,#f,s = setunion(s,v[n-(n/f[i])])); v[n] = s); apply(length,v); }
%o A332902 v332809 = A332809list(up_to);
%o A332902 A332809(n) = v332809[n];
%o A332902 A332902(n) = if(1==n,n,(A332809(n)-A332809(n-1)));
%Y A332902 Cf. A332809, A332903.
%K A332902 sign
%O A332902 1,8
%A A332902 _Antti Karttunen_, Apr 04 2020