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 A066540 The first of two consecutive primes with equal digital sums. 11
 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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The difference between the two primes ​​of the pair is a multiple of 18. - Antonio Roldán, Mar 13 2012 LINKS Harry J. Smith, Table of n, a(n) for n = 1..1000 G. L. Honaker, Jr. and C. Caldwell, Prime Curios! EXAMPLE a(1) = 523 because both it and the next prime, 541, have a digital sum of 10. MATHEMATICA Prime[ Select[Range[2000], Apply[ Plus, IntegerDigits[ Prime[ # ]]] == Apply[ Plus, IntegerDigits[ Prime[ # + 1]]] & ]] PROG (PARI) SumD(x)= { local(s=0); while (x>9, s+=x%10; x\=10); return(s + x) } { n=0; d=2; for (m=2, 10^10, s=SumD(prime(m)); if (s==d, write("b066540.txt", n++, " ", prime(m-1)); if (n==1000, return) ); d=s ) }  \\ Harry J. Smith, Feb 22 2010 (PARI) is_A066540(p)={my(n=nextprime(p+1)); (n-p)%18==0 & isprime(p) & A007953(p)==A007953(n)}  \\ M. F. Hasler, Oct 13 2012 CROSSREFS Subsequence of A117838. A069567 is a subsequence. Cf. A007513, A007953, A209396, A210629. Sequence in context: A095651 A117838 A031936 * A209875 A080912 A183830 Adjacent sequences:  A066537 A066538 A066539 * A066541 A066542 A066543 KEYWORD base,easy,nonn AUTHOR Jason Earls, Jan 06 2002 STATUS approved

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Last modified October 19 21:28 EDT 2019. Contains 328244 sequences. (Running on oeis4.)