This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A073735 #16 Dec 11 2021 02:10:56 %S A073735 579,968,1065,1221,1428,1604,2092,2117,2126,2236,2406,2872,2935,3048, %T A073735 3330,3496,4085,4194,4434,4697,4887,5148,5446,5846,5910,6484,6846, %U A073735 7355,7448,7468,7773,7939,8324,8746,8923,8957,9018,9093,9369,10242,10318 %N A073735 Numbers k such that the k-th term of the EKG sequence (A064413(k)) has more than one controlling prime. %C A073735 These are the k such that A073734(k) is not a prime power. %H A073735 Michael De Vlieger, <a href="/A073735/b073735.txt">Table of n, a(n) for n = 1..10000</a> %H A073735 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 A073735 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 A073735 <a href="/index/Ed#EKG">Index entries for sequences related to EKG sequence</a> %e A073735 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 A073735 Cf. A064413, A064740, A073734. %K A073735 easy,nonn %O A073735 1,1 %A A073735 _David Wasserman_, Aug 06 2002