OFFSET
1,3
LINKS
Ray Chandler, Table of n, a(n) for n = 1..10000
EXAMPLE
a(2) = 1 = 0 + 1 (two but no fewer terms)
a(3) = 6 = 1 + 2 + 3 (three but no fewer terms)
a(4) = 10 = 1 + 2 + 3 + 4 (four but no fewer terms)
a(5) = 20 = 2 + 3 + 4 + 5 + 6 (five but no fewer terms)
a(6) = 0, since no number needs six but no fewer terms
a(7) = 28 = 1 + 2 + 3 + 4 + 5 + 6 + 7 (seven but no fewer terms)
CROSSREFS
KEYWORD
nonn
AUTHOR
Martin Renner, Mar 14 2016
STATUS
approved