A188897 a(n) = lcm(n, n+1, n+2, n+3, n+4, n+5, n+6, n+7)/840.

0, 1, 3, 3, 33, 429, 429, 429, 858, 4862, 14586, 25194, 25194, 1938, 21318, 490314, 245157, 72105, 312455, 148005, 148005, 4292145, 390195, 525915, 2103660, 4628052, 6052068, 672452, 2017356, 2573868

Offset

0,3

Links

Table of n, a(n) for n=0..29.

Formula

a(n) = (n+7)!/(5040*(n-1)!*p(n)*q(n)*(1+6*f(n))), n > 1 where

p(n) = 8*3^((n-1)^2 mod 3),

q(n) = 4*(((n-2)^4 mod 5 +(n-1)^4) mod 5)-3, and

f(n) = 1-(n^6 mod 7).

Maple

seq(lcm(n, n+1, n+2, n+3, n+4, n+5, n+6, n+7)/840, n=0..30);
p:=n-> 8*3^((n-1)^2 mod 3):q:=n-> 4*(((n-2)^4 mod 5 +(n-1)^4)mod5)-3:f:=n-> 1-(n^6 mod 7): seq((n+7)!/(5040*(n-1)!*p(n)*q(n)*(1+6*f(n))), n=1..30)

Crossrefs

Cf. A189144.

Sequence in context: A344934 A086667 A067098 * A088060 A368387 A213281

Adjacent sequences: A188894 A188895 A188896 * A188898 A188899 A188900

Keyword

nonn

Author

Gary Detlefs, Apr 19 2011

Status

approved