A102420 Number of partitions of n into exactly k = 5 parts with each part p <= 5.
0, 0, 0, 0, 0, 1, 1, 2, 3, 5, 6, 8, 9, 11, 11, 12, 11, 11, 9, 8, 6, 5, 3, 2, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 0
Examples
a(8) = 3 because we can write 8=1+1+1+2+3 or 1+1+1+1+4 or 1+1+2+2+2.
Programs
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Mathematica
Table[Count[IntegerPartitions[n,{5}],?(Max[#]<6&)],{n,0,110}] (* _Harvey P. Dale, Nov 29 2012 *)
Formula
G.f.:z^5+z^6+2*z^7+3*z^8+5*z^9+6*z^10+8*z^11+9*z^12+11*z^13 +11*z^14 +12*z^15+ 11*z^16+11*z^17+9*z^18+8*z^19+6*z^20+5*z^21+3*z^22 +2*z^23 +z^24 +z^25.
Comments