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A175277
Base-5 pandigital primes: primes having at least one of each digit 0,1,2,3,4, when written in base 5.
8
3319, 3323, 3347, 3469, 3491, 3539, 3547, 3559, 3571, 3607, 3613, 3617, 3691, 3823, 3847, 3863, 4019, 4079, 4139, 4327, 4423, 4483, 4493, 4519, 4523, 4603, 4759, 4903, 4951, 5039, 5059, 5107, 5113, 5147, 5179, 5227, 5273, 5279, 5351, 5477, 5507, 5527
OFFSET
1,1
COMMENTS
Terms in this sequence have at least 6 digits in base 5, i.e., are larger than 5^5, since sum(d_i 5^i) = sum(d_i) (mod 4), and 0+1+2+3+4 is divisible by 2. So the smallest ones should be of the form "10...." in base 5, where "...." is a permutation of "1234". By chance the identical permutation already yields a prime, i.e. a(1) = "101234" in base 5.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000 (terms 1..2500 from Harvey P. Dale)
Alonso Del Arte, Classifications of prime numbers - By representation in specific bases, OEIS Wiki as of Mar 19 2010.
MATHEMATICA
Select[Prime[Range[800]], Min[DigitCount[#, 5]]>0&] (* Harvey P. Dale, Mar 10 2019 *)
PROG
(PARI) base(n, b=5, s=0)={local(a=[n%b]); while(0<n\=b, a=concat(n%b, a)); if(s, s=32*s+23; Strchr(vectorsmall(#a, i, if(a[i]>9, s, 48)+a[i])), a)}
forprime(p=5^5, 5^6, #Set(base(p, 5))==5 & print1(p", "))
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, May 27 2010
STATUS
approved