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A233438
Primorial(n) mod compositorial(n), that is, A002110(n) mod A036691(n).
0
0, 2, 6, 30, 210, 2310, 30030, 510510, 9699690, 223092870, 6469693230, 200560490130, 2153462358810, 72490129383210, 1958274892758030, 58665460642891410, 50035643372444730, 19221664375883039070, 1123712842678138983270, 27456249893723439879090, 350421246400567367415390
OFFSET
0,2
COMMENTS
The sequence of numbers k such that a(k) > a(k+1) begins: 15, 42, 645, 805, 1566, 5430, 53698, ...
FORMULA
a(n) = A002110(n) mod A036691(n).
PROG
(PARI) a(n)=my(c, p, N); N=n; c=4; p=1; while(n>0, if(!isprime(c), p=p*c; n=n-1); c=c+1); prod(i=1, N, prime(i))%p \\ Ralf Stephan, Dec 21 2013
CROSSREFS
KEYWORD
nonn
AUTHOR
Alex Ratushnyak, Dec 09 2013
STATUS
approved