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A226531 Cubes that become prime when their least-significant (rightmost) digit is removed. 2

%I

%S 27,3375,4096,4913,35937,97336,110592,148877,421875,681472,1191016,

%T 1442897,1560896,2628072,3241792,3581577,3869893,4741632,5359375,

%U 8998912,10218313,12649337,16777216,16974593,21253933,26730899,31255875,32157432,43986977,45882712

%N Cubes that become prime when their least-significant (rightmost) digit is removed.

%H Christian N. K. Anderson, <a href="/A226531/b226531.txt">Table of n, a(n) for n = 1..10000</a>

%e 4096 = 16^3, and becomes the prime number 409 when truncated.

%o (R) library(gmp)trimR=function(x) { x=as.character(x); ifelse(nchar(x)<2,0,substr(x,1,nchar(x)-1)) }

%o y=as.bigz(rep(0,10000)); len=0; n=as.bigz(-1)

%o while(len<10000) if(isprime(trimR((n=n+1)^3))) y[(len=len+1)]=n^3

%Y Cf. A226090.

%Y Cf. A024770, A225873, A225885, A226354.

%K nonn,base

%O 1,1

%A _Kevin L. Schwartz_ and _Christian N. K. Anderson_, Jun 09 2013

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Last modified May 22 06:32 EDT 2019. Contains 323478 sequences. (Running on oeis4.)