OFFSET
1,1
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..10000
FORMULA
EXAMPLE
k| A292610(n) | a(n) | Sum
---------------------------------------------------------------------------------------
0| (= 0)
1| 1 + 3 + 6 = 10 (= 10)
2| 15 + 21 + 28 + 36 = 45 + 55 (= 100)
3| 66 + 78 + 91 + 105 + 120 = 136 + 153 + 171 (= 460)
4| 190 + 210 + 231 + 253 + 276 + 300 = 325 + 351 + 378 + 406 (= 1460)
5| 435 + 465 + 496 + 528 + 561 + 595 + 630 = 666 + 703 + 741 + 780 + 820 (= 3710)
MATHEMATICA
Block[{s = Array[{#, # + 3} &, 11] - 1, r}, r = PolygonalNumber@ Range@ Total@ Flatten@ s; Map[Function[{a, b}, {First@ #, Set[r, Drop[Last@ #, b]]} &@ TakeDrop[r, a]] @@ # &, s][[All, 1]] // Flatten] (* Michael De Vlieger, Sep 25 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 20 2017
STATUS
approved