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 A257762 Numbers n with property that A062234(n) = A062234(n+1). 8
 1, 3, 5, 7, 13, 26, 28, 43, 49, 64, 69, 78, 89, 93, 96, 116, 131, 134, 142, 148, 152, 155, 167, 182, 202, 206, 212, 225, 231, 234, 236, 238, 247, 253, 258, 281, 286, 302, 303, 311, 313, 330, 332, 333, 334, 336, 337, 356, 362, 384, 385, 390, 435, 438, 455, 458, 484, 492, 512, 516 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers n with property that 2*prime(n)-prime(n+1) = 2*prime(n+1)-prime(n+2), or 2*prime(n)+prime(n+2) = 3*prime(n+1). Numbers n with property that 2*A001223(n) = A001223(n+1). - Gionata Neri, May 22 2015 a(n) = A258432(m), where m such that A258383(m) = 2. - Reinhard Zumkeller, May 31 2015 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(1) = A258437(A258432(2)) = 1. MAPLE Primes:= select(isprime, [2, (2*i+1 \$ i=1..10^4)]): Gaps:= Primes[2..-1] - Primes[1..-2]: G2:= Gaps[2..-1] - 2*Gaps[1..-2]: ListTools:-SearchAll(0, G2); # Robert Israel, May 22 2015 MATHEMATICA Select[Range@ 600, 2 Prime[#] - Prime[# + 1] == 2 Prime[# + 1] - Prime[# + 2] &] (* Michael De Vlieger, May 11 2015 *) PROG (MAGMA) [n: n in [0..600] | 2*NthPrime(n)-NthPrime(n+1) eq 2*NthPrime(n+1)-NthPrime(n+2)]; // Vincenzo Librandi, May 12 2015 (Haskell) a257762 n = a257762_list !! (n-1) a257762_list = map a258432 \$ filter ((== 2) . a258383) [1..] -- Reinhard Zumkeller, May 31 2015 CROSSREFS Cf. A258383, A258432, A258437, A258469, A257762, A258449, A257892, A257951. Sequence in context: A154321 A024724 A024946 * A224222 A224221 A128547 Adjacent sequences:  A257759 A257760 A257761 * A257763 A257764 A257765 KEYWORD nonn AUTHOR Zak Seidov, May 07 2015 STATUS approved

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Last modified May 12 10:44 EDT 2021. Contains 343821 sequences. (Running on oeis4.)