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For k >= a(n), there are A048284(n) numbers expressible as a sum of exactly k-n k-gonal numbers.
1

%I #7 Mar 30 2012 19:00:08

%S 6,9,10,13,16,19,20,22,25,28,29,31,34,37,40,41,43,46,49,52,53,54,57,

%T 58,61,64,67,68,70,73,74,75,78,81,84,86,89,90,92,93,94,96,99,102,105,

%U 108,109,110,112,113,115,118,121,124,126,129,130,132,133,136,137,138,140,143,146,149,152

%N For k >= a(n), there are A048284(n) numbers expressible as a sum of exactly k-n k-gonal numbers.

%e For k >= 6, the 2 numbers 2k-1 and 5k-4 are the sum of at best k k-gonal numbers. Hence a(0) = 6.

%e For k >= 9, the 4 numbers k-1, 2k-2, 4k-4 and 5k-5 are the sum of at best k-1 k-gonal numbers. Hence a(1) = 9.

%e For k >= 10, the 6 numbers k-2, 2k-3, 3k-4, 4k-5, 5k-6 and 8k-9 are the sum of at best k-2 k-gonal numbers. Hence a(2) = 10.

%K nonn

%O 0,1

%A _David W. Wilson_

%E Definition corrected by _Jonathan Sondow_, Jun 27 2007