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A054212 a(n)^5 is the smallest fifth power whose decimal expansion digits occur with same frequency n. 3

%I

%S 0,2955,49995,10365589,75418384,2592877410,100661113419,3989342709778

%N a(n)^5 is the smallest fifth power whose decimal expansion digits occur with same frequency n.

%C Terms calculated by _Jeff Heleen_.

%H Patrick De Geest, <a href="http://www.worldofnumbers.com/samedigits.htm">Numbers whose digits occur with same frequency</a>

%e 2955^5 = 225313610074846875 and digits 0, 1, 2, 3, 4, 5, 6, 7, and 8 each occur twice.

%o (Python)

%o def agen(POW=5):

%o n = 1

%o while True:

%o k = 0

%o while True:

%o kpowstr = str(pow(k, POW))

%o q, r = divmod(len(kpowstr), n)

%o if r == 0:

%o ok = True

%o for d in set(kpowstr):

%o if kpowstr.count(d) != n:

%o ok = False; break

%o if ok: break

%o k += 1

%o else: # go to next multiple of n digits: (q+1)*n

%o k = max(k+1, int((10**((q+1)*n-1))**(1/POW)))

%o yield k

%o n += 1

%o g = agen() # call with POW=4, 3, 2 for A052093, A052071, A052069

%o print([next(g) for n in range(1, 5)]) # _Michael S. Branicky_, Dec 17 2020

%Y Cf. A054213, A052093, A052094, A052069, A052071.

%K nonn,base,hard,more

%O 1,2

%A _Patrick De Geest_, Feb 15 2000

%E Offset corrected by _Michel Marcus_, Aug 12 2015

%E a(7)-a(8) from _Michael S. Branicky_, Dec 17 2020

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Last modified July 24 09:52 EDT 2021. Contains 346273 sequences. (Running on oeis4.)