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A227654 Ruth-Aaron triples (1): sum of primes dividing n = sum of primes dividing (n+1) = sum of primes dividing (n+2). 0
89460294, 151165960539, 3089285427491, 6999761340223, 7539504384825 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(6) > 10^13. Taking into account primes multiplicity (A039752), the only triples up to 10^13 are those starting at 417162 and 6913943284.

LINKS

Table of n, a(n) for n=1..5.

Carlos Rivera, Puzzle 358. Ruth-Aaron Pairs Revisited, The Prime Puzzles and Problems Connection.

Eric Weisstein's World of Mathematics, Ruth-Aaron Pair

Wikipedia, Ruth-Aaron pair

EXAMPLE

7539504384825 = 3^2 * 5^2 * 7^2 * 43 * 251 * 63361,

7539504384826 = 2 * 19 * 367 * 10181 * 53101,

7539504384827 = 17 * 457 * 26309 * 36887 and

3 + 5 + 7 + 43 + 251 + 63361 = 2 + 19 + 367 + 10181 + 53101 = 17 + 457 + 26309 + 36887.

CROSSREFS

Cf. A006145, A039752.

Sequence in context: A054434 A164850 A253269 * A069318 A172573 A015367

Adjacent sequences: A227651 A227652 A227653 * A227655 A227656 A227657

KEYWORD

nonn

AUTHOR

Giovanni Resta, Jul 19 2013

STATUS

approved

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Last modified November 28 17:22 EST 2022. Contains 358421 sequences. (Running on oeis4.)