A210972 Sum of all region numbers of all parts of all partitions of n.
1, 5, 14, 43, 98, 255, 532, 1201, 2413, 4968, 9427, 18475
Offset: 1
Examples
For n = 5 we have: --------------------------------------------------- . Two arrangements k of the partitions of 5 --------------------------------------------------- 7 [5] [5] 6 [3+2] [3+2] 5 [4+1] [4 +1] 4 [2+1+1] [2+2 +1] 3 [3+1+1] [3 +1 +1] 2 [2+1+1+1] [2+1 +1 +1] 1 [1+1+1+1+1] [1+1+1 +1 +1] --------------------------------------------------- . Two arrangements . of the region numbers Sum of k of the partitions of 5 zone k --------------------------------------------------- 7 [7] [7] 7 6 [6,7] [6,7] 13 5 [5,7] [5, 7] 12 4 [4,5,7] [4,5, 7] 16 3 [3,5,7] [3, 5, 7] 15 2 [2,3,5,7] [2,3, 5, 7] 17 1 [1,2,3,5,7] [1,2,3, 5, 7] 18 --------------------------------------------------- The total sum is a(5) = 1+2^2+3^2+4+5^2+6+7^2 = 1+4+9+4+25+6+49 = 18+17+15+16+12+13+7 = 98.
Links
- Omar E. Pol, Illustration of the seven regions of 5
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