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A075904
Numbers k such that k^4 has k as a substring of its decimal expansion.
4
0, 1, 5, 6, 10, 25, 50, 60, 76, 83, 92, 100, 107, 211, 217, 250, 352, 363, 376, 500, 556, 600, 625, 636, 760, 863, 909, 935, 1000, 1531, 1636, 2263, 2500, 2503, 3630, 3760, 4342, 5000, 5001, 6000, 6250, 7245, 7600, 8578, 9350, 9376, 10000, 25000, 28206, 32213
OFFSET
1,3
LINKS
EXAMPLE
6^4 = 129_6, 83^4 = 4745_83_21, 2503^4 = 39_2503_37770081.
MATHEMATICA
Select[Range[10000], StringPosition[ToString[ #^4], ToString[ # ]] != {} &] (* Tanya Khovanova, Oct 11 2007 *)
ssQ[n_]:=Module[{idn=IntegerDigits[n], idn4=IntegerDigits[n^4]}, MemberQ[ Partition[ idn4, Length[ idn], 1], idn]]; Select[Range[10000], ssQ] (* Harvey P. Dale, Mar 13 2013 *)
PROG
(Python)
A075904_list, m = [0], [24, -36, 14, -1, 0]
for n in range(1, 10**9+1):
....for i in range(4):
........m[i+1] += m[i]
....if str(n) in str(m[-1]):
........A075904_list.append(n) # Chai Wah Wu, Nov 05 2014
CROSSREFS
Cf. A018834 (squares), A029942 (cubes), A075905 (5th powers).
Sequence in context: A035111 A035282 A075156 * A018834 A029943 A356760
KEYWORD
base,nonn
AUTHOR
Zak Seidov, Sep 27 2002
EXTENSIONS
More terms from Tanya Khovanova, Oct 11 2007
Added 0 to sequence by Chai Wah Wu, Nov 05 2014
STATUS
approved