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A178550
Primes with exactly one digit 1.
11
13, 17, 19, 31, 41, 61, 71, 103, 107, 109, 127, 137, 139, 149, 157, 163, 167, 173, 179, 193, 197, 199, 241, 251, 271, 281, 313, 317, 331, 401, 419, 421, 431, 461, 491, 521, 541, 571, 601, 613, 617, 619, 631, 641, 661, 691, 701, 719, 751, 761, 821, 881, 919
OFFSET
1,1
LINKS
PROG
(Python)
from sympy import isprime
print([i for i in range(1000) if str(i).count('1') == 1 and isprime(i)]) # Daniel Starodubtsev, Mar 29 2020
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, May 29 2010
STATUS
approved