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A077719
Primes which can be expressed as sum of distinct powers of 5.
9
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
OFFSET
1,1
COMMENTS
Primes whose base 5 representation contains only zeros and 1's.
LINKS
PROG
(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
print(aupton(37)) # Michael S. Branicky, May 31 2021
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Nov 19 2002
EXTENSIONS
More terms from Sascha Kurz, Jan 03 2003
a(36) and beyond from Michael S. Branicky, May 31 2021
STATUS
approved