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%I #20 Nov 30 2022 08:35:41
%S 1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,3,1,1,1,1,4,1,1,
%T 1,1,1,1,1,2,1,1,1,1,1,1,1,2,1,1,1,1,1,3,1,2,1,1,1,1,1,1,1,4,1,1,1,1,
%U 1,1,1,2,1,1,1,1,1,1,1,2,3,1,1,1,1,1,1,2,1,1,1,1,1,1,1,4,1,1,1,1,1,1,1,2,1
%N Multiplicative with a(p^e) = p^floor((e-1)/2).
%H Antti Karttunen, <a href="/A295657/b295657.txt">Table of n, a(n) for n = 1..20000</a>
%F a(1) = 1; for n > 1, a(n) = A020639(n)^A004526(A067029(n)-1) * a(A028234(n)).
%F a(n) = A000188(A003557(n)).
%F a(n) = 1 iff A212793(n) = 1.
%F Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 15/Pi^2 = 1.519817... (A082020). - _Amiram Eldar_, Nov 30 2022
%t Array[Apply[Times, FactorInteger[#] /. {p_, e_} /; p > 0 :> p^Floor[(e - 1)/2]] &, 105] (* _Michael De Vlieger_, Nov 28 2017 *)
%o (Scheme, with memoization-macro definec) (definec (A295657 n) (if (= 1 n) 1 (* (expt (A020639 n) (A004526 (- (A067029 n) 1))) (A295657 (A028234 n)))))
%o (PARI) a(n) = {my(f = factor(n)); prod(i = 1, #f~, f[i,1]^floor((f[i,2]-1)/2));} \\ _Amiram Eldar_, Nov 30 2022
%Y Cf. A000188, A003557, A004526, A020639, A028234, A067029, A295658, A295659.
%Y Cf. A004709 (positions of ones), A082020, A212793.
%Y Cf. also A008834, A053150, A061704.
%K nonn,mult
%O 1,8
%A _Antti Karttunen_, Nov 28 2017