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A295000
Prime time primes (of the form HMMSS with primes H < 24 and MM, SS < 60) such that the corresponding number of seconds after midnight is also prime.
7
20231, 20297, 20353, 20507, 20719, 20753, 20771, 21107, 21313, 21379, 21713, 21767, 21773, 21929, 21937, 22343, 22367, 22397, 22961, 22973, 23131, 23143, 23167, 23173, 23197, 23719, 23741, 23743, 23747, 23753, 24137, 24179, 24337, 24359, 24371, 24379
OFFSET
1,1
COMMENTS
Could be called "super prime time primes": all of H, MM, SS, HMMSS (6-digit clock display) and H*3600 + MM*60 + SS (seconds after midnight) are prime.
This sequence lists the prime time primes A295013 for which the number of seconds A295003 is prime. These are also the times HMMSS (obtained through A055643) which correspond to the subset A295002 of primes in A295003.
Sequence A295002 lists the number of seconds after midnight corresponding to the "prime times" = 6-digit clock displays listed here.
Sequences A295003 and A295004 list the number of seconds after midnight corresponding to the prime time primes A295013 and prime time numbers A295014, i.e., primes and all numbers of the form HMMSS where H < 24 and MM, SS < 60 are prime.
LINKS
M. F. Hasler, Table of n, a(n) for n = 1..404 (complete sequence).
FORMULA
a(n) = A055643(A295002(n)) ; A295000 = { A295013(k) | A295003(k) is prime }.
EXAMPLE
The smallest prime of the form HMMSS, with H, MM, SS and H*3600 + MM*60 + SS also prime, is a(1) = 20231, corresponding to a prime number A295002(1) = H*3600 + MM*60 + SS = 7351 (the first prime in A295003) of seconds after midnight.
PROG
(PARI) apply( A055643, A295002) /* or */ select( p->isprime(A292579(p)), A295013)
KEYWORD
nonn,base,fini,full
AUTHOR
M. F. Hasler, Jan 15 2018
STATUS
approved