A286333 Primes p where all the cyclic shifts of their digits to the left also produce primes except the last one before reaching p again.
19, 23, 29, 41, 43, 47, 53, 59, 61, 67, 83, 89, 101, 103, 107, 127, 149, 157, 163, 181, 191, 307, 317, 331, 359, 367, 701, 709, 727, 739, 757, 761, 787, 797, 907, 937, 941, 947, 983, 1103, 1109, 1123, 1181, 1301, 1319, 1327, 1949, 1951, 1979, 1987, 1993, 3121, 3187, 3361, 3373, 3701
Offset: 1
Examples
1123 is a member as all the cyclic shifts of its digits to the left result are primes (1231, 2311) except the last one (3112) before reaching the original prime.
Links
- Chai Wah Wu, Table of n, a(n) for n = 1..144
Programs
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Mathematica
cyclDigs[k_]:= FromDigits/@ NestList[RotateLeft, IntegerDigits[k], IntegerLength[k]-1]; lftSftNearCircPrmsInBtw[m_, n_]:= ParallelMap[If[ AllTrue[Most[cyclDigs[#]], PrimeQ] && Not@ PrimeQ[Last[cyclDigs[#]]], #, Nothing] &, Prime @ Range[PrimePi[m], PrimePi[n]]]; lftSftNearCircPrmsInBtw[19, 10^7]
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Python
from itertools import product from sympy import isprime A286333_list = [] for l in range(14): for w in product('1379',repeat=l): for d in '0123456789': for t in '1379': s = ''.join(w)+d+t n = int(s) for i in range(l+1): if not isprime(int(s)): break s = s[1:]+s[0] else: if n > 10 and not isprime(int(s)): A286333_list.append(n) # Chai Wah Wu, May 21 2017
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