# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a331381 Showing 1-1 of 1 %I A331381 #6 Jan 17 2020 10:37:53 %S A331381 1,1,1,1,1,3,1,5,2,6,6,5,5,7,4,7,7,7,10,8,9,6,10,9,9,15,7,12,10,14,10, %T A331381 10,8,8,15,10,7,16,13,9,10,14,12,10,8,14,11,13,11,16,15,14,15,15,10, %U A331381 14,18,11,12,13,13,18,21,15,16,19,16,15,8,17,17 %N A331381 Number of integer partitions of n whose sum of primes of parts is divisible by their product of parts. %e A331381 The a(n) partitions for n = 1, 5, 7, 8, 9, 13, 14: %e A331381 1 221 43 311111 63 7411 65111 %e A331381 311 511 11111111 441 721111 322211111 %e A331381 11111 3211 711 43111111 311111111111 %e A331381 22111 42111 421111111 11111111111111 %e A331381 1111111 2211111 3211111111 %e A331381 111111111 22111111111 %e A331381 1111111111111 %t A331381 Table[Length[Select[IntegerPartitions[n],Divisible[Plus@@Prime/@#,Times@@#]&]],{n,0,30}] %Y A331381 The Heinz numbers of these partitions are given by A331382. %Y A331381 Numbers divisible by the sum of their prime factors are A036844. %Y A331381 Partitions whose product is divisible by their sum are A057568. %Y A331381 Numbers divisible by the sum of their prime indices are A324851. %Y A331381 Product of prime indices is divisible by sum of prime indices: A326149. %Y A331381 Partitions whose Heinz number is divisible by their sum are A330950. %Y A331381 Sum of prime factors is divisible by sum of prime indices: A331380 %Y A331381 Partitions whose product is equal to their sum of primes are A331383. %Y A331381 Product of prime indices equals sum of prime factors: A331384. %Y A331381 Cf. A000040, A001414, A324850, A330953, A330954, A331378, A331379, A331415, A331416. %K A331381 nonn %O A331381 0,6 %A A331381 _Gus Wiseman_, Jan 16 2020 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE