The "two-infinite" array
A new array for the OEIS? 0 +1 +3 +7 +11 +5 +14 ... -1 +2 -4 +4 -6 +9 ... -3 +6 -8 -10 -15 ... -9 -14 -2 -25 ... -5 -12 -23 ... -7 -35 ... -28 ... ... The idea is to insert in an infinite “triangular” array, all integers from - ∞ to +∞, with no duplicates. [This is now A330656 in the OEIS, thanks to Carole Dubois ] We start, as usual, in the upper left corner with 0. The array now is filled with those two rules: Rule 1 ) we always try to extend the upper row with the smallest positive integer a(n) no