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Smallest number with the property that exactly n of its divisors are partition numbers.
5

%I #36 Jun 23 2023 03:41:47

%S 1,2,6,15,42,30,270,210,462,1848,3696,11088,2310,9240,18480,55440,

%T 83160,166320,498960,2494800,17463600,331808400,4418290800

%N Smallest number with the property that exactly n of its divisors are partition numbers.

%e a(3) = 6 because 6 is the smallest number with the property that exactly three of its divisors are partition numbers. The divisors of 6 are 1, 2, 3, 6, and 1, 2, 3 are also partition numbers.

%e a(5) = 42 because 42 is the smallest number with the property that exactly five of its divisors are partition numbers. The divisors of 42 are 1, 2, 3, 6, 7, 14, 21, 42, and 1, 2, 3, 7, 42 are members of A000041.

%Y Cf. A000041, A236102, A236103, A236105, A236107, A236108, A236111.

%K nonn,more,hard

%O 1,2

%A _Omar E. Pol_, Jan 22 2014

%E a(12) and a(15)-a(18) from _Alois P. Heinz_, Jan 22 2014

%E a(19)-a(22) from _Giovanni Resta_, Feb 06 2014

%E a(23) from _Amiram Eldar_, Jun 23 2023