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A308561
Numbers with no 0 digit that are divisible by the sum of any two of their digits at distinct positions.
1
1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 18, 21, 24, 27, 36, 42, 45, 48, 54, 63, 72, 81, 84, 252, 1212, 1512, 2112, 2424, 2772, 3636, 4224, 4848, 6216, 6336, 8316, 8448, 11112, 11116, 21252, 22212, 22224, 22512, 33336, 34944, 43344, 44424, 44448, 66636, 77112, 86688, 88848, 99792, 111216, 111636
OFFSET
1,2
COMMENTS
Without the constraint of having no digit 0, the terms would be much more dense, cf. A308560.
EXAMPLE
12 is divisible by 1 + 2 = 3, but 11 is not divisible by 1 + 1.
1512 is divisible by 1 + 5 = 6, 1 + 1 = 2, 1 + 2 = 3 and 5 + 2 = 7.
For single-digit numbers there is no such sum and therefore no divisibility condition, so they are in the sequence.
PROG
(PARI) is(n, d=digits(n))={vecmin(d)&&n>9&&0==n%lcm(concat(vector(-1+n=#d, i, t=d[1+n-i]; vector(n-i, j, t+d[j]))))}
CROSSREFS
Sequence in context: A217973 A097518 A097569 * A095160 A356350 A288528
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Jun 07 2019
STATUS
approved