A048523 Primes for which only one iteration of 'Prime plus its digit sum equals a prime' is possible.

13, 19, 37, 53, 71, 73, 97, 103, 127, 163, 181, 233, 271, 307, 383, 389, 431, 433, 499, 509, 563, 587, 631, 701, 743, 787, 811, 857, 859, 947, 1009, 1049, 1061, 1087, 1153, 1171, 1223, 1283, 1423, 1483, 1489, 1553, 1597, 1601, 1607, 1733, 1801, 1861, 1867

Offset

1,1

Comments

Sequence A048519 lists the primes for which at least (rather than exactly) one iteration of A062028 is "possible". See A048524 .. A048527 and A320878 .. A320880 for further subsequences, and A090009 for the list of their initial terms, starting chains of length >= 3 .. 9. - M. F. Hasler, Nov 09 2018

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

prime 1999 -> 1999 + (1+9+9+9) = prime 2027 -> next iteration yields composite 2038.

Mathematica

ppd1Q[n_]:=PrimeQ[Rest[NestList[#+Total[IntegerDigits[#]]&, n, 2]]] == {True, False}; Select[Prime[Range[300]], ppd1Q] (* Harvey P. Dale, Nov 10 2011 *)

Crossrefs

Cf. A047791, A048519.

Sequence in context: A057749 A040070 A322923 * A307627 A000922 A107188

Adjacent sequences: A048520 A048521 A048522 * A048524 A048525 A048526

Keyword

nonn,base

Author

Patrick De Geest, May 15 1999

Status

approved