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%I #9 Aug 25 2024 10:00:46
%S 1,2,1,2,1,2,3,2,3,2,5,2,3,4,1,2,2,4,9,2,3,6,11,2,5,4,9,4,7,2,5,3,5,3,
%T 3,4,9,10,3,2,5,4,7,6,3,12,23,2,21,6,2,4,13,10,5,4,9,8,29,2,15,6,3,3,
%U 3,6,33,3,11,4,35,4,9,10,5,10,15,4,39,2,27,6,41,4,2,8,7,6,11,4,3,12,5,24
%N Number of powers of 16 modulo n.
%H Amiram Eldar, <a href="/A054716/b054716.txt">Table of n, a(n) for n = 1..10000</a>
%t a[n_] := IntegerExponent[8*n, 16] + MultiplicativeOrder[16, n/2^IntegerExponent[n, 2]]; Array[a, 100] (* _Amiram Eldar_, Aug 25 2024 *)
%Y Cf. A054703 (base 2), A054704 (3), A054705 (4), A054706 (5), A054707 (6), A054708 (7), A054709 (8), A054717 (9), A054710 (10), A351524 (11), A054712 (12), A054713 (13), A054714 (14), A054715 (15).
%K easy,nonn
%O 1,2
%A _Henry Bottomley_, Apr 20 2000