A340113 Acronym primes: primes which are the sums of primes and also equal the concatenation of the initial digits of these primes.

2, 3, 5, 7, 127, 131, 137, 139, 149, 151, 157, 173, 179, 211, 233, 251, 271, 277, 281, 311, 331, 353, 421, 431, 433, 443, 463, 521, 523, 541, 547, 571, 577, 613, 631, 641, 653, 733, 743, 751, 757, 761, 769, 827, 853, 857, 877, 887, 953, 971, 983

Offset

1,1

Links

Table of n, a(n) for n=1..51.

Eric Angelini, Sum of peculiar primes, math-fun mailing list, Dec 24, 2020.

Example

The single-digit primes trivially satisfy the constraint.
127 is prime and the concatenation of the initial digits of the primes (19, 29, 79) and also equal to their sum.
131 is prime and the concatenation of the initial digits of the primes (109, 3, 17) and also equal to their sum.

Prog

(PARI) select( {is_A340113(n)=is_A340112(n) && isprime(n)}, [1..999]) \\ or: {A340113_upto(N)=select(is_A340112, primes([1, N]))}

Crossrefs

These are the primes in the sequence of prime-acronyms A340112.

Sequence in context: A117058 A067173 A357262 * A090718 A167853 A117703

Adjacent sequences: A340110 A340111 A340112 * A340114 A340115 A340116

Keyword

nonn,base

Author

Eric Angelini and M. F. Hasler, Dec 28 2020

Status

approved