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A225296 Numbers divisible by their first digit cubed (excluding those whose first digit is 1). 3
24, 200, 208, 216, 224, 232, 240, 248, 256, 264, 272, 280, 288, 296, 324, 351, 378, 448, 500, 648, 2000, 2008, 2016, 2024, 2032, 2040, 2048, 2056, 2064, 2072, 2080, 2088, 2096, 2104, 2112, 2120, 2128, 2136, 2144, 2152, 2160, 2168, 2176, 2184, 2192, 2200, 2208 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers where floor(n/10^floor(log(n)))^3 | n.

LINKS

Christian N. K. Anderson, Table of n, a(n) for n = 1..10000

Christian N. K. Anderson, Ulam Spiral of first 10000 terms.

EXAMPLE

448 is divisible by 4^3.

MATHEMATICA

dfdcQ[n_]:=Module[{fidn=IntegerDigits[n][[1]]}, fidn!=1&&Divisible[ n, fidn^3]]; Select[Range[2500], dfdcQ] (* Harvey P. Dale, Jan 13 2019 *)

PROG

(R) x=0; y=rep(0, 1000); len=0

firstdig<-function(x) as.numeric(substr(as.character(x), 1, 1))

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

while(len<1000) if((fd=firstdig((x=x+1)))>1) if(isint(x/fd^3)) y[(len=len+1)]=x

CROSSREFS

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

Sequence in context: A126519 A260358 A198396 * A048355 A132458 A055857

Adjacent sequences:  A225293 A225294 A225295 * A225297 A225298 A225299

KEYWORD

nonn,base

AUTHOR

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

STATUS

approved

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Last modified May 12 10:54 EDT 2021. Contains 343821 sequences. (Running on oeis4.)