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A215021 a(n) = A118478(n)*(A118478(n)+1) divided by the product of the first n primes. 2

%I

%S 1,1,1,1,19,17,1,409,604,82,20951,229931,411012,39080794,4382914408,

%T 6345486566,45119290746,581075656330,8672770990,869561574799171,

%U 71853663603175593,25509154378676494,24040267482771436703,102403319155457392955,11302410854347731819765

%N a(n) = A118478(n)*(A118478(n)+1) divided by the product of the first n primes.

%C When floor(A214089(n) / 2) = A118478(n), a(n) = A215085(n).

%Y Cf. A118478, A002110.

%K nonn

%O 1,5

%A _N. J. A. Sloane_, Aug 02 2012, following a comment in A118478 made by _Robert G. Wilson v_ on May 13 2006

%E a(18)-a(25) from _J. Stauduhar_, Aug 17 2012

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Last modified June 24 11:45 EDT 2021. Contains 345416 sequences. (Running on oeis4.)