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A125903
a(n) = product of the first n primes which are coprime to n.
1
2, 15, 70, 1155, 6006, 1616615, 1385670, 111546435, 2156564410, 742073813481, 674612557710, 2180460221945005, 1006366256282310, 2327797034085003195, 128184023343614175938, 961380175077106319535, 6899316550553351234310
OFFSET
1,1
EXAMPLE
The first 6 primes which are coprime to 6 are 5,7,11,13,17,19. So a(6)=5*7*11*13*17*19 = 1616615.
MATHEMATICA
f[n_] := Block[{c = n, k = 0, p, t = 1}, While[c > 0, k++; While[p = Prime[k]; GCD[p, n] > 1, k++ ]; c--; t *= p; ]; t]; Table[f[n], {n, 17}] (* Ray Chandler, Dec 14 2006 *)
CROSSREFS
Sequence in context: A146757 A091135 A056037 * A268644 A178321 A007232
KEYWORD
nonn
AUTHOR
Leroy Quet, Dec 13 2006
EXTENSIONS
Extended by Ray Chandler, Dec 14 2006
STATUS
approved