A330653 The prime numbers whose digit sum, adjacent digit sum concatenation, and adjacent digit difference concatenation are also primes.
29, 41, 47, 61, 83, 101, 263, 281, 401, 463, 601, 607, 661, 809, 821, 863, 1129, 1303, 2063, 2267, 3121, 3181, 3301, 3343, 4001, 4603, 5309, 5581, 6007, 6043, 6803, 6863, 7129, 7309, 8009, 8681, 8821, 9721, 9967, 10903, 10909, 14143, 16903, 17209, 18521, 19421, 20063, 20201, 20407, 20807, 21143, 24281, 25147
Offset: 1
Examples
a(1) = 29, as 2 + 9 = 11, '2 + 9' = 11, '|2 - 9|' = 7, and 29, 11, 7 are all prime. a(7) = 263, as 2 + 6 + 3 = 11, '2 + 6' + '6 + 3' = 89, '|2 - 6|' + '|6 - 3|' = 43, and 263, 11, 89, 43 are all prime. a(25) = 4001, as 4 + 0 + 0 + 1 = 5, '4 + 0' + '0 + 0' + '0 + 1' = 401, '|4 - 0|' + '|0 - 0|' + '|0 - 1|' = 401, and 4001, 5, 401 are all prime.
Links
- Giovanni Resta, Table of n, a(n) for n = 1..10000
- Chris K. Caldwell, How many primes are there?
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