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%I #7 Jul 29 2020 16:38:18
%S 45,63,99,117,147,153,171,207,261,279,315,325,333,369,387,423,425,477,
%T 495,531,549,585,603,639,657,693,711,725,735,747,765,801,819,847,855,
%U 873,909,925,927,963,981,1017,1025,1035,1071,1125,1143,1179,1197,1233,1251,1287,1305,1325,1341,1359,1395,1413,1449,1467,1503
%N Odd numbers k such that gcd(A336551(k), A326143(k)) is equal to A336551(k).
%C Is the intersection with A336554 empty?
%H Antti Karttunen, <a href="/A336553/b336553.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/O#opnseqs">Index entries for sequences where odd perfect numbers must occur, if they exist at all</a>
%o (PARI)
%o A007947(n) = factorback(factorint(n)[, 1]);
%o A326143(n) = (sigma(n)-A007947(n)-n);
%o A336551(n) = { my(f=factor(n)); for(i=1, #f~, f[i, 2] = f[i, 2]-1); (factorback(f)-1); };
%o isA336553(n) = if(!(n%2),0, my(u=A336551(n)); (u==gcd(u,A326143(n))));
%Y Odd terms in A336552.
%Y Cf. A336554.
%K nonn
%O 1,1
%A _Antti Karttunen_, Jul 28 2020
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