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%I #17 Nov 22 2023 22:33:34
%S 2,4,8,16,24,64,48,256,96,144,192,4096,240,16384,768,576,480,262144,
%T 720,1048576,960,2304,12288,16777216,1440,5184,49152,3600,3840,
%U 1073741824,2880,4294967296,3360,36864,786432,20736,5040,274877906944,3145728,147456,6720,4398046511104,11520,17592186044416
%N Least k such that A048272(k) = -n.
%C All terms are even.
%F a(n) = 2 * A187941(n).
%F a(n) = 4 * A005179(n) for n > 0.
%o (PARI) a048272(n) = sumdiv(n, d, if (d%2, 1, -1));
%o a(n) = {my(k=1); while (a048272(k) != -n, k++); k;} \\ _Michel Marcus_, May 27 2018
%Y Cf. A005179, A048272, A187941.
%Y Cf. A038547 (similar but with n instead of -n).
%K nonn
%O 0,1
%A _Seiichi Manyama_, May 26 2018
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