1,3

a(1)=1 as 10 is the only 2-digit multiple of 1 whose digits sum to 1, while a(3)=3 as the multiples 12, 21 and 30 have the property.

Sequence in context: A068695 A110787 A139002 this_sequence A038500 A091840 A083985

Adjacent sequences: A139375 A139376 A139377 this_sequence A139379 A139380 A139381

base,full,nonn,fini

Ian Duff (ianfduff(AT)yahoo.co.uk), Jun 08 2008