NO_SQUARES wrote: Triangular numbers are numbers of the form $1 + 2 + . . . + n$ with positive integer $n$, that is $1, 3, 6, 10$, . . . . Find the largest non-triangular positive integer number that cannot be represented as the sum of various triangular numbers. Proposed by A. Golovanov Does "various" mean "distinct" ?

pco wrote: NO_SQUARES wrote: Triangular numbers are numbers of the form $1 + 2 + . . . + n$ with positive integer $n$, that is $1, 3, 6, 10$, . . . . Find the largest non-triangular positive integer number that cannot be represented as the sum of various triangular numbers. Proposed by A. Golovanov Does "various" mean "distinct" ? Yes, it does. Thank you!

I think this is the easiest solution https://proofwiki.org/wiki/Integers_not_Sum_of_Distinct_Triangular_Numbers