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A048284 For k >= A048283(n), there are a(n) numbers expressible as a sum of exactly k-n k-gonal numbers. 1
2, 4, 6, 7, 9, 9, 12, 14, 14, 15, 17, 19, 20, 20, 21, 23, 26, 26, 27, 27, 29, 31, 33, 34, 35, 35, 35, 37, 39, 41, 42, 44, 44, 44, 44, 46, 48, 51, 52, 54, 54, 54, 54, 54, 55, 57, 61, 62, 63, 64, 64, 65, 65, 65, 67, 69, 72, 73, 75, 75, 76, 77, 77, 77, 77, 78, 81, 84, 85, 86, 87, 88, 90, 90, 90, 90, 90 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..76.

EXAMPLE

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

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) = 4.

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) = 6.

CROSSREFS

Sequence in context: A088458 A177866 A065853 * A026516 A289012 A186493

Adjacent sequences:  A048281 A048282 A048283 * A048285 A048286 A048287

KEYWORD

nonn

AUTHOR

David W. Wilson

EXTENSIONS

Definition corrected by Jonathan Sondow, Jun 27 2007

STATUS

approved

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Last modified December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)