Hello MathFun, Do you like numbers? If two terms hereunder, placed one after the other, sum up to a prime, erase them. The non-erased terms will rebuild the starting sequence: Two, three, six, seven, two, seven, six, three, six, three, two, seven, two, seven, two, three, six, three, six, three, six, seven, two, seven, two, seven, two, seven, six, three, six, three, six, three, six, three, two, seven, two, seven, two, seven, two, seven, two, three, six, three, six, three, six, three, six, three, six, seven, two, seven, two, seven, two, seven, two, seven, two, seven, six, three, six, three, six, three, six, three, six, three, six, three, two, ... (Two, three), (six, seven), two, (seven, six), three, six, (three, two), seven, two, seven, (two, three), six, three, six, three, (six, seven), two, seven, two, seven, two, (seven, six), three, six, three, six, three, six, (three, two), seven, two, seven, two, seven, two, seven, (two, three), six, three, six, three, six, three, six, three, (six, seven), two, seven, two, seven, two, seven, two, seven, two, (seven, six), three, six, three, six, three, six, three, six, three, six, (three, two), ... Do you prefer letters? If two terms above, placed one after the other, share a letter, erase them. The non-erased terms will rebuild the starting sequence. Question: is this the lexicographically first such sequence? Best, É.