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Primes p such that each of the decimal numbers p^k for k=1..7 has exactly two 1s.
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%I #11 Mar 23 2024 20:20:40

%S 14591,11225237,12050149,13801993,89186231,119474633,125361787,

%T 126196387,127491563,128153203,137018603,137399173,157801387,

%U 213873157,299431019,731831437,1146462257,1149800857,1236918523,1452210367,1712996843,1719567953,1918333693,1955601727

%N Primes p such that each of the decimal numbers p^k for k=1..7 has exactly two 1s.

%C Subsequence of A175972 which in turn is subsequence of A175964.

%o (Python)

%o from somewhere import primegen

%o for p in primegen():

%o if all(str(p**k).count('1') == 2 for k in range(1, 8)):

%o print(p) # _Lucas A. Brown_, Mar 23 2024

%Y Cf. A175964, A175972.

%K base,nonn

%O 1,1

%A _Zak Seidov_, Nov 01 2010

%E a(19)-a(24) from _Lucas A. Brown_, Mar 23 2024

%E Definition clarified by _N. J. A. Sloane_, Mar 23 2024.