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%I #10 Oct 19 2017 10:38:29
%S 1,2,15,6,105,30,1155,770,36465,210,15015,6006,255255,2310,8580495,
%T 102102,4849845,72930,20056049013,74364290,5898837945,30030,
%U 3234846615,881790,195282582495,510510,218257003965,20281170,100280245065,17160990,934482952262145,6614136163635
%N Least k such that the Jacobsthal function A048669(k) = n.
%C Except for a(1) and a(2), the same as A070971. It appears that a(2n)=2a(n) for odd n. Because the primorial numbers (A002110) yield record values of the Jacobsthal function, we have a(A048670(n))=A002110(n). Note that numbers in this sequence up to n=18 have the form p#, p#/2, p#/q, or p#/(2q), where p and q are primes with 2<q<p and p# denotes the product of the primes up to p.
%Y Cf. A048669, A070971, A002110, A048670.
%K nonn
%O 1,2
%A _T. D. Noe_, Mar 28 2007
%E a(19) onwards from _Don Reble_, Oct 17 2013