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Multiplicative with a(p^e) = A019565(A193231(e)).
7

%I #10 Nov 02 2017 15:36:53

%S 1,2,2,6,2,4,2,3,6,4,2,12,2,4,4,10,2,12,2,12,4,4,2,6,6,4,3,12,2,8,2,5,

%T 4,4,4,36,2,4,4,6,2,8,2,12,12,4,2,20,6,12,4,12,2,6,4,6,4,4,2,24,2,4,

%U 12,15,4,8,2,12,4,8,2,18,2,4,12,12,4,8,2,20,10,4,2,24,4,4,4,6,2,24,4,12,4,4,4,10,2,12,12,36,2,8,2,6,8

%N Multiplicative with a(p^e) = A019565(A193231(e)).

%H Antti Karttunen, <a href="/A293443/b293443.txt">Table of n, a(n) for n = 1..65537</a>

%H <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>

%F a(1) = 1; for n > 1, a(n) = A019565(A193231(A067029(n))) * a(A028234(n)).

%F For all n >= 1, A007814(a(n)) = A293439(n).

%F For all k in A270428, A007814(a(k)) = A001221(k).

%o (PARI)

%o A019565(n) = {my(j,v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ This function from _M. F. Hasler_

%o A193231(n) = { my(x='x); subst(lift(Mod(1, 2)*subst(Pol(binary(n), x), x, 1+x)), x, 2) }; \\ And this from _Franklin T. Adams-Watters_

%o vecproduct(v) = { my(m=1); for(i=1,#v,m *= v[i]); m; };

%o A293443(n) = vecproduct(apply(e -> A019565(A193231(e)), factorint(n)[, 2]));

%o (Scheme, with memoization-macro definec)

%o (definec (A293443 n) (if (= 1 n) n (* (A019565 (A193231 (A067029 n))) (A293443 (A028234 n)))))

%Y Cf. A019565, A028234, A067029, A193231.

%Y Cf. also A270428, A293442, A293231, A293439.

%K nonn,mult

%O 1,2

%A _Antti Karttunen_, Oct 31 2017