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A077719
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Primes which can be expressed as sum of distinct powers of 5.
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9
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5, 31, 131, 151, 631, 751, 3251, 3881, 16381, 19381, 19501, 19531, 78781, 78901, 81281, 81401, 81901, 82031, 93901, 94531, 97001, 97501, 97651, 390751, 390781, 393901, 394501, 406381, 468781, 469501, 471901, 472631, 484531, 485131, 487651, 1953151, 1953901
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OFFSET
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1,1
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COMMENTS
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Primes whose base 5 representation contains only zeros and 1's.
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LINKS
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PROG
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(Python)
from sympy import isprime
def aupton(terms):
k, alst = 0, []
while len(alst) < terms:
k += 1
t = sum(5**i*int(di) for i, di in enumerate((bin(k)[2:])[::-1]))
if isprime(t): alst.append(t)
return alst
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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