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%I #16 Dec 11 2021 02:10:56
%S 579,968,1065,1221,1428,1604,2092,2117,2126,2236,2406,2872,2935,3048,
%T 3330,3496,4085,4194,4434,4697,4887,5148,5446,5846,5910,6484,6846,
%U 7355,7448,7468,7773,7939,8324,8746,8923,8957,9018,9093,9369,10242,10318
%N Numbers k such that the k-th term of the EKG sequence (A064413(k)) has more than one controlling prime.
%C These are the k such that A073734(k) is not a prime power.
%H Michael De Vlieger, <a href="/A073735/b073735.txt">Table of n, a(n) for n = 1..10000</a>
%H Michael De Vlieger, <a href="/A073735/a073735.txt">Mathematica code</a> for this sequence, based on Lagarias-Rains-Sloane 2002 paper, page 4-5.
%H J. C. Lagarias, E. M. Rains and N. J. A. Sloane, <a href="https://arxiv.org/abs/math/0204011">The EKG sequence</a>, Exper. Math. 11 (2002), 437-446; arXiv:math/0204011 [math.NT], 2002.
%H <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a>
%e A064413(578) = 620, which is divisible by the primes 2, 5 and 31. So by definition, A064413(579) is the smallest number not already in A064413 that is divisible by 2, 5, or 31. This number is 610, which is divisible by both 2 and 5, so these are both called controlling primes of A064413(579).
%Y Cf. A064413, A064740, A073734.
%K easy,nonn
%O 1,1
%A _David Wasserman_, Aug 06 2002