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A031125 Number of proper factorizations of p1^n*p2^2, where p1 and p2 are distinct primes. 1

%I #11 May 01 2017 15:10:09

%S 1,3,8,15,28,46,76,117,180,266,391,559,796,1110,1540,2105,2862,3845,

%T 5141,6807,8972,11732,15274,19752,25442,32581,41568,52769,66756,84077,

%U 105554,131994,164565,204449,253291,312798,385284,473182,579721,708352

%N Number of proper factorizations of p1^n*p2^2, where p1 and p2 are distinct primes.

%H Ray Chandler, <a href="/A031125/b031125.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = A000291(n) - 1 = A028422(2^n*3^2). - _Ray Chandler_, May 01 2017

%Y Cf. A000291, A028422.

%K nonn

%O 0,2

%A _Jeff Burch_

%E Offset changed to 0 and more terms added by _Ray Chandler_, May 01 2017

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Last modified March 3 00:46 EST 2024. Contains 370499 sequences. (Running on oeis4.)