OFFSET
0,3
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
KEYWORD
nonn
AUTHOR
Gary Detlefs, Apr 19 2011
STATUS
approved