# A053052 (b-file synthesized from sequence entry) 1 1 2 21 3 123 4 4321 5 12345 6 654321 7 1234567 8 87654321 9 123456789 10 10987654321 11 1234567891011 12 121110987654321 13 12345678910111213 14 1413121110987654321 15 123456789101112131415