# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a035650 Showing 1-1 of 1 %I A035650 #16 Aug 16 2020 20:15:23 %S A035650 0,0,0,0,0,0,0,1,0,0,1,0,1,3,0,1,3,1,3,6,1,3,8,3,7,12,3,9,16,7,15,22, %T A035650 9,19,30,16,29,40,20,38,54,32,54,69,41,70,93,61,95,118,78,124,156,110, %U A035650 163,195,141,211,255,192,271,317,245,349,409,323,441,506,412,562,644 %N A035650 Number of partitions of n into parts 6k+3 and 6k+5 with at least one part of each type. %H A035650 Alois P. Heinz, Table of n, a(n) for n = 1..1000 (first 125 terms from Robert Price) %F A035650 G.f.: (-1 + 1/Product_{k>=0} (1 - x^(6 k + 3)))*(-1 + 1/Product_{k>=0} (1 - x^(6 k + 6))). - _Robert Price_, Aug 16 2020 %p A035650 b:= proc(n, i, t, s) option remember; `if`(n=0, t*s, `if`(i<1, 0, %p A035650 b(n, i-1, t, s)+(h-> `if`(h in {3, 5}, add(b(n-i*j, i-1, %p A035650 `if`(h=3, 1, t), `if`(h=5, 1, s)), j=1..n/i), 0))(irem(i, 6)))) %p A035650 end: %p A035650 a:= n-> b(n$2, 0$2): %p A035650 seq(a(n), n=1..75); # _Alois P. Heinz_, Aug 14 2020 %t A035650 nmax = 71; s1 = Range[0, nmax/6]*6 + 3; s2 = Range[0, nmax/6]*6 + 5; %t A035650 Table[Count[IntegerPartitions[n, All, s1~Join~s2], %t A035650 x_ /; ContainsAny[x, s1 ] && ContainsAny[x, s2 ]], {n, 1, nmax}] (* _Robert Price_, Aug 14 2020 *) %t A035650 nmax = 71; l = Rest@CoefficientList[Series[(-1 + 1/Product[(1 - x^(6 k + 3)), {k, 0, nmax}])*(-1 + 1/Product[(1 - x^(6 k + 5)), {k, 0, nmax}]), {x, 0, nmax}], x] (* _Robert Price_, Aug 16 2020 *) %Y A035650 Cf. A035441-A035468, A035618-A035649, A035651-A035699. %K A035650 nonn %O A035650 1,14 %A A035650 _Olivier GĂ©rard_ # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE