211223

Appears in sequences

• Juxtapose pairs of primes.at n=23A007795
• Partition the concatenation 235711131719232931...of prime numbers into successive strings such that the n-th string is a multiple of prime(n) and > prime(n).at n=7A077304
• Semiprimes which are concatenation of two consecutive primes.at n=16A244057