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A106711 Smaller prime of the set of two consecutive primes each of whose sum of digits is prime. 0
2, 3, 5, 7, 23, 41, 43, 61, 83, 131, 137, 151, 173, 191, 193, 197, 223, 227, 263, 281, 311, 313, 317, 331, 353, 373, 397, 401, 443, 461, 463, 571, 593, 599, 601, 641, 643, 733, 751, 797, 821, 823, 827, 881, 883, 911, 971, 1013, 1031, 1033, 1091, 1093, 1097, 1103 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

a(5)=23 is a term because sum of digits of two consecutive primes i.e. 23 and 29 is prime i.e. 2+3=5 and 2+9=11.

MATHEMATICA

Select[Partition[Prime[Range[200]], 2, 1], PrimeQ[Total[IntegerDigits[ #[[1]]]]] && PrimeQ[Total[IntegerDigits[#[[2]]]]]&][[All, 1]] (* or *) Prime[#]&/@SequencePosition[Table[If[PrimeQ[Total[IntegerDigits[n]]], 1, 0], {n, Prime[Range[200]]}], {1, 1}][[All, 1]] (* The second program requires Mathematica version 10 or later, but is more efficient because it only requires testing each prime for its sum of digits once. *) (* Harvey P. Dale, Jul 27 2017 *)

CROSSREFS

Sequence in context: A100552 A210566 A155873 * A235110 A048398 A059170

Adjacent sequences:  A106708 A106709 A106710 * A106712 A106713 A106714

KEYWORD

base,nonn

AUTHOR

Shyam Sunder Gupta, May 14 2005

EXTENSIONS

Definition clarified by Harvey P. Dale, Jul 27 2017

STATUS

approved

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Last modified September 15 18:22 EDT 2019. Contains 327082 sequences. (Running on oeis4.)