A155148 Numbers n such that n^4 has exactly 2 different decimal digits.

2, 3, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000, 1000000000, 10000000000

Offset

1,1

Links

Table of n, a(n) for n=1..12.

Maple

for n from 1 do convert(convert(n^4, base, 10), set) ; if nops(%) = 2 then print(n) ; fi; od: # R. J. Mathar, Feb 08 2009

Prog

(Python)
A155148_list, m = [], [24, -36, 14, -1, 0]
for n in range(1, 10**6+1):
....for i in range(4):
........m[i+1] += m[i]
....if len(set(str(m[-1]))) == 2:
........A155148_list.append(n) # Chai Wah Wu, Nov 05 2014

Crossrefs

Cf. A155149, A155150

Sequence in context: A270356 A333332 A229220 * A076927 A064647 A119810

Adjacent sequences: A155145 A155146 A155147 * A155149 A155150 A155151

Keyword

nonn,base

Author

Dmitry Kamenetsky, Jan 21 2009

Extensions

Two more terms from R. J. Mathar, Feb 08 2009

a(9)-a(12) from Charles R Greathouse IV, Aug 01 2010

Status

approved