%I #17 Mar 04 2024 01:15:03
%S 1,2,3,4,5,6,7,8,9,10,12,16,20,24,30,32,36,40,48,50,60,64,70,80,90,96,
%T 110,112,132,170,184,220,224,225,252,264,275,312,330,336,340,342,396,
%U 414,418,440,441,448,510,550,621,624,660,665,680,684,770,812,825,828
%N Numbers m such that m/k is an integer. m = (x_1 x_2 ... x_r) where x_i are digits of m, k = x_1*r + x_2*(r-1) + ... + x_r*1.
%C From _Michel Marcus_, Aug 18 2015: (Start)
%C Integers m such that m and m+1 are in the sequence: 1, 2, 3, 4, 5, 6, 7, 8, 9, 224, 440, 2046, 3604, 4255, 6255, 10511, 11190, ...
%C Integers m such that m, m+1 and m+2 are in the sequence: 1, 2, 3, 4, 5, 6, 7, 8, 140607, 411904, 1099448, 1101150, 2109074, 2110158, ...
%C (End)
%H Paolo P. Lava, <a href="/A180479/b180479.txt">Table of n, a(n) for n = 1..10000</a>
%e For m=132, r=3, 132/(1*3+3*2+2*1)=12, so m=132 belongs to the sequence.
%t Select[Range[1000], Mod[#, Total[ IntegerDigits[#] Reverse@ Range@ IntegerLength@ #]] == 0 &] (* _Giovanni Resta_, Aug 18 2015 *)
%o (PARI) isok(n) = {my(d = digits(n)); ! (n % sum(kk=1, #d, d[kk]*(#d-kk+1)));} \\ _Michel Marcus_, Aug 18 2015
%Y Cf. A005349, A007602, A180468.
%K base,easy,nonn
%O 1,2
%A _Ctibor O. Zizka_, Sep 07 2010
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