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A061215 a(n)= product of all odd composite numbers between n-th prime and (n+1)-st prime. 2

%I #9 Mar 12 2015 19:10:04

%S 1,1,1,9,1,15,1,21,675,1,1155,39,1,45,2499,3135,1,4095,69,1,5775,81,

%T 7395,803985,99,1,105,1,111,2978730129375,129,17955,1,429774345,1,

%U 23715,25599,165,28899,30975,1,1196537265,1,195,1,361878338745

%N a(n)= product of all odd composite numbers between n-th prime and (n+1)-st prime.

%H Harry J. Smith, <a href="/A061215/b061215.txt">Table of n, a(n) for n=1,...,2000</a>

%e a(9) = 675 = 25 * 27, as 23 is the 9th prime and 29 is the 10th prime.

%o (PARI) for(n=1,60,p=1:for(k=prime(n)+1, prime(n+1)-1,if(k%2==1,p=p*k)):print1(p","))

%o (PARI) { n=0; q=2; forprime (p=3, prime(2001), a=1; for (i=q + 1, p - 1, if (i%2==1, a*=i)); q=p; write("b061215.txt", n++, " ", a) ) } \\ _Harry J. Smith_, Jul 19 2009

%K nonn

%O 1,4

%A _Amarnath Murthy_, Apr 22 2001

%E More terms from _Ralf Stephan_, Mar 31 2003

%E First term removed by _Harry J. Smith_, Jul 19 2009

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Last modified August 15 05:59 EDT 2024. Contains 375172 sequences. (Running on oeis4.)