A225281 T(n,k) = Number of distinct values of the sum of i*(i-1) over n realizations of i in 0..k.

1, 2, 1, 3, 3, 1, 4, 6, 4, 1, 5, 9, 9, 5, 1, 6, 14, 15, 12, 6, 1, 7, 19, 26, 21, 15, 7, 1, 8, 25, 36, 36, 27, 18, 8, 1, 9, 32, 49, 51, 46, 33, 21, 9, 1, 10, 39, 66, 71, 66, 56, 39, 24, 10, 1, 11, 47, 85, 94, 92, 81, 66, 45, 27, 11, 1, 12, 56, 103, 123, 122, 113, 96, 76, 51, 30, 12, 1, 13, 64

Offset

1,2

Comments

Table starts

.1..2..3..4..5...6...7...8...9..10..11..12..13..14..15...16...17...18...19...20

.1..3..6..9.14..19..25..32..39..47..56..64..76..87..99..109..123..138..152..167

.1..4..9.15.26..36..49..66..85.103.130.152.180.214.247..276..320..362..399..444

.1..5.12.21.36..51..71..94.123.150.188.223.263.310.359..409..465..523..586..653

.1..6.15.27.46..66..92.122.160.195.243.290.344.403.466..532..605..680..762..848

.1..7.18.33.56..81.113.150.196.240.298.356.423.495.571..653..744..835..936.1040

.1..8.21.39.66..96.134.178.232.285.353.422.501.586.676..773..881..989.1107.1232

.1..9.24.45.76.111.155.206.268.330.408.488.579.677.781..893.1017.1143.1278.1423

.1.10.27.51.86.126.176.234.304.375.463.554.657.768.886.1013.1153.1296.1449.1614

.1.11.30.57.96.141.197.262.340.420.518.620.735.859.991.1133.1289.1449.1620.1804

Links

R. H. Hardin, Table of n, a(n) for n = 1..1325

Formula

Empirical: column k is n*k*(k-1)/2 - A225288(k) for large n (n>37 is sufficient through k=389).

Crossrefs

Sequence in context: A131251 A144400 A373169 * A057145 A134394 A322967

Adjacent sequences: A225278 A225279 A225280 * A225282 A225283 A225284

Keyword

nonn,tabl

Author

R. H. Hardin, May 04 2013

Status

approved