A328792 Numbers that are not the difference between any triangular number and the largest square that does not exceed it.
4, 7, 8, 13, 16, 18, 22, 23, 25, 26, 31, 33, 34, 37, 38, 40, 43, 47, 48, 49, 52, 58, 59, 60, 61, 63, 64, 67, 68, 70, 73, 76, 79, 81, 83, 85, 86, 88, 92, 93, 94, 97, 98, 99, 102, 103, 106, 108, 112, 113, 114, 115, 118, 121, 123, 124, 125, 130, 133, 134, 138
Offset: 1
Keywords
Examples
For any triangular number t, let f(t) = t - floor(sqrt(t))^2. 0 is not a term: for each term t in A001110, f(t) = 0. 1 is not a term: for each term t > 1 in A164055, f(t) = 1. 2 is not a term: for each term t in A214838, f(t) = 2. 3 is not a term: for each term t > 3 in A328791, f(t) = 3. 4 is a term, however: there exists no triangular number t such that f(t) = 4.