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A209875 Numbers n and n+18 are consecutive primes with equal digital sum. 1
523, 1069, 1259, 1759, 1913, 2503, 3803, 4159, 4373, 4423, 4463, 4603, 4703, 4733, 5059, 5209, 6229, 6529, 6619, 7159, 7433, 7459, 8191, 9109, 9749, 9949, 10691, 10753, 12619, 12763, 12923, 13763, 14033, 14107, 14303, 14369, 15859, 15973, 16529, 16673, 16903 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A066540 and A209663 (A066540 contains same consecutive primes with differences greater than 18. A209663 contains same not consecutive primes)

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..3000

EXAMPLE

19013 is in the sequence because 19013 is prime, 19013+18=19031 is the next prime, and sum_of_digits(19013) = sum_of_digits(19031) = 14.

MATHEMATICA

Select[Prime[Range[2000]], Total[IntegerDigits[#]] == Total[IntegerDigits[NextPrime[#]]] &] (* T. D. Noe, Mar 14 2012 *)

PROG

(PARI) sumdig(p)={ local(v, s=0); v=Vec(Str(p)); for(i=1, #v, s+=eval(v[i])); return(s)}

{forprime(n=3, 10^5, m=nextprime(n+1); if(m-n==18&&sumdig(n)==sumdig(m), print1(n, " ")))}

/* Antonio Roldán, Dec 21 2012 */

CROSSREFS

Cf. A066540, A209663.

Sequence in context: A117838 A031936 A066540 * A080912 A183830 A207212

Adjacent sequences:  A209872 A209873 A209874 * A209876 A209877 A209878

KEYWORD

nonn,base,less

AUTHOR

Antonio Roldán, Mar 14 2012

STATUS

approved

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Last modified July 25 04:48 EDT 2017. Contains 289779 sequences.