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A297792 a(n) = Sum_{d|n} min(d, n/d)^2.

%I A297792 #27 Jan 10 2018 15:20:02
%S A297792 1,2,2,6,2,10,2,10,11,10,2,28,2,10,20,26,2,28,2,42,20,10,2,60,27,10,
%T A297792 20,42,2,78,2,42,20,10,52,96,2,10,20,92,2,100,2,42,70,10,2,132,51,60,
%U A297792 20,42,2,100,52,140,20,10,2,182,2,10,118,106,52,100,2,42,20
%N A297792 a(n) = Sum_{d|n} min(d, n/d)^2.
%H A297792 Seiichi Manyama, <a href="/A297792/b297792.txt">Table of n, a(n) for n = 1..10000</a>
%F A297792 From _Michel Marcus_, Jan 09 2018: (Start)
%F A297792 a(p) = 2, for prime p.
%F A297792 a(2p) = 10, for odd prime p. (End)
%F A297792 a(r*p) = 2 + 2*r^2, where r, p are primes and p > r. - _Bruno Berselli_, Jan 09 2018
%t A297792 a[n_] := Block[{d = Divisors@n}, Plus @@ (Min[#, n/#]^2 & /@ d)]; Array[a, 70] (* _Robert G. Wilson v_, Jan 06 2018 *)
%o A297792 (PARI) {a(n) = sumdiv(n, d, min(d, n/d)^2)}
%Y A297792 Sum_{d|n} min(d, n/d)^k: A117004 (k=1), this sequence (k=2), A297793 (k=3), A297794 (k=4), A297795 (k=5).
%K A297792 nonn
%O A297792 1,2
%A A297792 _Seiichi Manyama_, Jan 06 2018