OFFSET
2,2
COMMENTS
EXAMPLE
a(30)=6 because 30 = T(30)-T(29)=T(11)-T(8)=T(9)-T(5)=T(8)-T(3) and T(3)=6 is the least minuend.
MATHEMATICA
T=#(#+1)/2&; T[Sort[{k, j}/.{ToRules[Reduce[{T[k]-T[j]\[Equal]#, 0<j<k}, {j, k}, Integers]]}][[1, 2]]]&/@Range[2, 100]
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Pein (petsie(AT)dordos.net), Mar 30 2008
STATUS
approved