# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a258323 Showing 1-1 of 1 %I A258323 #30 Nov 01 2018 18:00:01 %S A258323 1,0,2,0,3,0,5,6,0,7,10,0,11,29,0,13,43,30,0,17,94,42,0,19,128,136,0, %T A258323 23,231,293,0,29,279,551,210,0,31,484,892,330,0,37,584,1765,852,0,41, %U A258323 903,2570,1826,0,43,1051,4273,4207,0,47,1552,6747,6595,2310 %N A258323 Sum T(n,k) over all partitions lambda of n into k distinct parts of Product_{i:lambda} prime(i); triangle T(n,k), n>=0, 0<=k<=A003056(n), read by rows. %H A258323 Alois P. Heinz, Rows n = 0..500, flattened %e A258323 T(6,2) = 43 because the partitions of 6 into 2 distinct parts are {[5,1], [4,2]} and prime(5)*prime(1) + prime(4)*prime(2) = 11*2 + 7*3 = 22 + 21 = 43. %e A258323 Triangle T(n,k) begins: %e A258323 1 %e A258323 0, 2; %e A258323 0, 3; %e A258323 0, 5, 6; %e A258323 0, 7, 10; %e A258323 0, 11, 29; %e A258323 0, 13, 43, 30; %e A258323 0, 17, 94, 42; %e A258323 0, 19, 128, 136; %e A258323 0, 23, 231, 293; %e A258323 0, 29, 279, 551, 210; %p A258323 g:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, expand( %p A258323 add(g(n-i*j, i-1)*(ithprime(i)*x)^j, j=0..min(1, n/i))))) %p A258323 end: %p A258323 T:= n-> (p-> seq(coeff(p, x, i), i=0..degree(p)))(g(n$2)): %p A258323 seq(T(n), n=0..20); %t A258323 g[n_, i_] := g[n, i] = If[n==0, 1, If[i<1, 0, Expand[Sum[g[n-i*j, i-1] * (Prime[i]*x)^j, {j, 0, Min[1, n/i]}]]]]; T[n_] := Function[p, Table[ Coefficient[p, x, i], {i, 0, Exponent[p, x]}]][g[n, n]]; Table[T[n], {n, 0, 20}] // Flatten (* _Jean-François Alcover_, Jan 06 2017, after _Alois P. Heinz_ *) %Y A258323 Columns k=0-10 give: A000007, A000040, A025129(n+1), A258358, A258359, A258360, A258361, A258362, A258363, A258364, A258365. %Y A258323 Row sums give A147655. %Y A258323 T(n*(n+1)/2,n) = A002110(n). %Y A258323 T(n^2,n) = A321267(n). %Y A258323 Cf. A000217, A003056, A145518, A246867. %K A258323 nonn,tabf %O A258323 0,3 %A A258323 _Alois P. Heinz_, May 26 2015 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE