A180479 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.

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, 110, 112, 132, 170, 184, 220, 224, 225, 252, 264, 275, 312, 330, 336, 340, 342, 396, 414, 418, 440, 441, 448, 510, 550, 621, 624, 660, 665, 680, 684, 770, 812, 825, 828

Offset

1,2

Comments

From Michel Marcus, Aug 18 2015: (Start)

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, ...

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, ...

(End)

Links

Paolo P. Lava, Table of n, a(n) for n = 1..10000

Example

For m=132, r=3, 132/(1*3+3*2+2*1)=12, so m=132 belongs to the sequence.

Mathematica

Select[Range[1000], Mod[#, Total[ IntegerDigits[#] Reverse@ Range@ IntegerLength@ #]] == 0 &] (* Giovanni Resta, Aug 18 2015 *)

Prog

(PARI) isok(n) = {my(d = digits(n)); ! (n % sum(kk=1, #d, d[kk]*(#d-kk+1))); } \\ Michel Marcus, Aug 18 2015

Crossrefs

Cf. A005349, A007602, A180468.

Sequence in context: A322856 A280863 A059765 * A193456 A143289 A064807

Adjacent sequences: A180476 A180477 A180478 * A180480 A180481 A180482

Keyword

base,easy,nonn

Author

Ctibor O. Zizka, Sep 07 2010

Status

approved