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Numbers with no 0 digit that are divisible by the sum of any two of their digits at distinct positions.
1

%I #14 Jan 14 2021 21:17:30

%S 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,

%T 1512,2112,2424,2772,3636,4224,4848,6216,6336,8316,8448,11112,11116,

%U 21252,22212,22224,22512,33336,34944,43344,44424,44448,66636,77112,86688,88848,99792,111216,111636

%N Numbers with no 0 digit that are divisible by the sum of any two of their digits at distinct positions.

%C Without the constraint of having no digit 0, the terms would be much more dense, cf. A308560.

%e 12 is divisible by 1 + 2 = 3, but 11 is not divisible by 1 + 1.

%e 1512 is divisible by 1 + 5 = 6, 1 + 1 = 2, 1 + 2 = 3 and 5 + 2 = 7.

%e For single-digit numbers there is no such sum and therefore no divisibility condition, so they are in the sequence.

%o (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]))))}

%Y Cf. A308560, A308534.

%K nonn,base

%O 1,2

%A _M. F. Hasler_, Jun 07 2019