A154874 Numbers k such that k^3 contains every digit exactly twice.

2158479, 2190762, 2205528, 2219322, 2301615, 2330397, 2336268, 2345811, 2358828, 2359026, 2367609, 2388534, 2389119, 2389638, 2397132, 2428986, 2504736, 2524974, 2536152, 2583258, 2590125, 2607222, 2620827, 2622012, 2647866, 2649369, 2658636, 2671593

Offset: 1

Author

Zhining Yang, Jan 16 2009

Keywords

• base
• easy
• fini
• full
• nonn

Comments

This sequence has 138 terms.

Examples

			2358828^3 = 13124683009764879552, which contains each digit 0..9 exactly twice.
		

Links

• Nathaniel Johnston, Table of n, a(n) for n = 1..138 (full sequence)

Crossrefs

Cf. A054038, A074205, A154532, A154566, A154871, A154873.

Programs

Maple

lim:=floor((10^20)^(1/3)): for j from ceil((10^19)^(1/3)) to lim do d:=convert(j^3,base,10): doubdig:=true: for k from 0 to 9 do if(numboccur(d,k)<>2)then doubdig:=false:break: fi: od: if(doubdig)then print(j); fi: od: # Nathaniel Johnston, May 28 2011

Mathematica

With[{cmin=Ceiling[Surd[10^19,3]],cmax=Floor[Surd[10^20,3]]},Select[ Range[ cmin, cmax], Union[ DigitCount[#^3]]=={2}&]] (* Harvey P. Dale, Nov 17 2018 *)