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A391734

Right edge of triangle A240673: a(n) = A002110(n-1) * A079276(n).

1, 4, 6, 120, 210, 6930, 450450, 9189180, 193993800, 2677114440, 116454478140, 5415133233510, 51945166943670, 1521251317636050, 562558737261811290, 1229779565176982820, 130356633908760178920, 19227603501542126390700, 4456958491657464897364260, 23574964653240801167637270, 33476449807601937658044923400, 814593611984980483012426469400

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OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..349

Index entries for sequences related to primorial numbers.

FORMULA

Apparently, for n >= 3, a(n) = A245458(n) - 2.

PROG

(PARI)

A002110(n) = prod(i=1, n, prime(i));

A079276(n) = lift(prod(i=1, n-1, Mod(1/prime(i), prime(n))));