A114549 Prime numbers p for which (sum of the digits of p) + (number of the digits of p) is a prime.

2, 23, 29, 41, 47, 83, 89, 101, 103, 107, 109, 127, 149, 163, 167, 181, 211, 233, 239, 251, 257, 271, 277, 293, 307, 347, 349, 367, 383, 389, 419, 431, 433, 439, 457, 479, 491, 503, 509, 521, 523, 541, 547, 563, 569, 587, 613, 617, 619, 631, 653, 659, 673

Offset

1,1

Links

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

Example

89 is in the sequence because (1) it is a prime number, (2) the sum of the digits is 8+9=17, the number of digits is 2 and (3) 17+2=19, which is a prime number.

Mathematica

Select[Prime[Range[150]], PrimeQ[Total[IntegerDigits[#]]+ IntegerLength[ #]]&] (* Harvey P. Dale, Jan 28 2015 *)

Prog

(PARI) isok(p) = isprime(p) && isprime(sumdigits(p) + #digits(p)); \\ Michel Marcus, Feb 26 2014

Crossrefs

Sequence in context: A355430 A226016 A235150 * A235148 A208325 A255564

Adjacent sequences: A114546 A114547 A114548 * A114550 A114551 A114552

Keyword

base,nonn

Author

Luc Stevens (lms022(AT)yahoo.com), Apr 20 2006

Extensions

Corrected by Harvey P. Dale, Jan 28 2015

Status

approved