A328621 - OEIS

%I #6 Oct 23 2019 16:41:59

%S 1,1,9,1,25,9,49,1,3,25,121,9,169,49,225,1,289,3,361,25,441,121,529,9,

%T 625,169,1,49,841,225,961,1,1089,289,1225,3,1369,361,1521,25,1681,441,

%U 1849,121,75,529,2209,9,2401,625,2601,169,2809,1,3025,49,3249,841,3481,225,3721,961,147,1,4225,1089,4489,289,4761,1225,5041,3,5329

%N Multiplicative with a(p^e) = p^(2e mod p).

%H Antti Karttunen, <a href="/A328621/b328621.txt">Table of n, a(n) for n = 1..16384</a>

%o (PARI) A328621(n) = { my(f = factor(n)); for(k=1, #f~, f[k,2] = ((2*f[k,2])%f[k,1])); factorback(f); };

%Y Cf. A011262, A327938, A328618 (a bijective variant).

%K nonn,mult

%O 1,3

%A _Antti Karttunen_, Oct 23 2019