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A225299 Numbers divisible by the square of each digit. 2
1, 11, 12, 36, 111, 112, 128, 144, 212, 216, 224, 333, 432, 448, 612, 1111, 1112, 1116, 1212, 1296, 1332, 1424, 2112, 2144, 2212, 2224, 2232, 2916, 3132, 3312, 3636, 4112, 4144, 4224, 4288, 4464, 6336, 6624, 8128, 8448, 9396, 11111, 11112, 11133, 11172, 11212 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Includes all repunits.

LINKS

Christian N. K. Anderson, Table of n, a(n) for n = 1..5000

EXAMPLE

a(7) 128 is divisible by 1^2, by 2^2, and by 8^2.

MATHEMATICA

d[n_]:=IntegerDigits[n]; t={}; Do[If[!MemberQ[d[n], 0] && Union[Mod[n, d[n]^2]] == {0}, AppendTo[t, n]], {n, 11220}]; t (* Jayanta Basu, May 15 2013 *)

Select[Range[12000], DigitCount[#, 10, 0]==0&&And@@Divisible[ #, IntegerDigits[ #]^2]&] (* Harvey P. Dale, Jul 16 2018 *)

PROG

(R) isint<-function(x) x==as.integer(x)

sqalldig<-function(x) as.numeric(strsplit(as.character(x), "")[[1]])^2

divby<-function(x) ifelse(length(grep(0, x))>0, F, all(isint(x/sqalldig(x))))

which(sapply(1:1000, divby))

CROSSREFS

Cf. A132359, A034709, A034837, A005349, A007602, A034838.

Sequence in context: A244068 A041252 A041250 * A290336 A300405 A248323

Adjacent sequences:  A225296 A225297 A225298 * A225300 A225301 A225302

KEYWORD

nonn,base

AUTHOR

Kevin L. Schwartz and Christian N. K. Anderson, May 04 2013

STATUS

approved

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Last modified October 21 16:25 EDT 2019. Contains 328302 sequences. (Running on oeis4.)