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Numbers k such that A276086(k) is a sum of distinct primorial numbers.
6

%I #23 Jul 02 2021 01:56:03

%S 0,1,2,3,4,9,30,39,212,249,421,2312,2559,30045,32589,510511,512820,

%T 543099,1021050,9729723,10242789,233335659,446185742

%N Numbers k such that A276086(k) is a sum of distinct primorial numbers.

%C Numbers k such that A276086(k) is in A276156, i.e., numbers k for which A328828(A276086(k)) is zero, i.e., numbers k such that in the primorial base expansion of A276086(k) there are no digits larger than 1.

%C Numbers k for which A276087(k) is squarefree.

%C No more terms below 2^31.

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%o (PARI)

%o A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };

%o A328828(n) = { my(i=1, p=2); while(n, if((n%p)>1, return(i)); i++; n = n\p; p = nextprime(1+p)); (0); };

%o isA328836(n) = !A328828(A276086(n));

%Y Sequence A328833 sorted into ascending order.

%Y Cf. A008966, A276086, A276087, A276156, A328828, A328832, A328833.

%Y Positions of zeros in A328829 and in A328844, positions of ones in A328389.

%Y Cf. A143293 (a subsequence).

%Y All the terms of A328313 are included in this sequence, like also in A328837.

%K nonn,hard,more

%O 1,3

%A _Antti Karttunen_, Oct 29 2019