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A277200 Even terms in A260442 (in A260443).

%I A277200 #18 Oct 26 2016 15:12:11
%S A277200 2,6,18,30,90,210,270,450,630,2310,6750,6930,9450,15750,20250,22050,
%T A277200 30030,47250,90090,330750,510510,727650,1212750,1531530,1653750,
%U A277200 2668050,3543750,4961250,8489250,9699690,18191250,24806250,25467750,29099070,40020750,53156250,57881250,104053950,173423250,173643750
%N A277200 Even terms in A260442 (in A260443).
%C A277200 All odd terms larger > 1 in A260442 can be obtained from these terms by shifting their prime factorization some number of steps towards larger primes with A003961.
%o A277200 (PARI)
%o A277200 allocatemem(2^30);
%o A277200 A061395(n) =  if(1==n, 0, primepi(vecmax(factor(n)[, 1]))); \\ After _M. F. Hasler_'s code for A006530.
%o A277200 A048675(n) = my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; \\ _Michel Marcus_, Oct 10 2016
%o A277200 A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From _Michel Marcus_
%o A277200 A260443(n) = if(n<2, n+1, if(n%2, A260443(n\2)*A260443(n\2+1), A003961(A260443(n\2))));
%o A277200 isA277200(n) = (!(n%2) && (omega(n) == A061395(n)) && (A260443(A048675(n)) == n));
%o A277200 i=1; n=0; while(i < 100, n++; if(isA277200(n), write("b277200.txt", i, " ", n); i++));
%Y A277200 Cf. A003961, A260442, A260443.
%Y A277200 Sequence A277324 sorted into ascending order.
%Y A277200 Subsequence of A055932.
%Y A277200 Cf. A002110, A277317 (subsequences, apart from their initial terms).
%Y A277200 Also all terms of A277318 apart from initial 3 are included in this sequence.
%K A277200 nonn
%O A277200 1,1
%A A277200 _Antti Karttunen_, Oct 14 2016