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 A088070 Numbers sandwiched between two numbers having the same number of prime divisors. 6
 3, 4, 6, 8, 10, 11, 12, 13, 18, 19, 21, 23, 24, 25, 26, 27, 28, 30, 34, 35, 37, 39, 42, 45, 47, 48, 49, 51, 53, 55, 56, 57, 60, 64, 72, 73, 75, 76, 80, 81, 82, 86, 87, 92, 93, 94, 95, 97, 99, 102, 105, 107, 108, 116, 117, 118, 123, 126, 131, 134, 135, 138, 139, 142, 143, 144 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsidiary sequence: (1) Start of the first run of a string of n successive integers in this sequence. Conjecture: For every k there is a string of k successive integers. LINKS Giovanni Resta, Table of n, a(n) for n = 1..10000 FORMULA a(n) = A063464(n) + 1. EXAMPLE 11 is a member as 10 and 12 both have two prime divisors. 26 is a member as 25 and 27 both have one each prime divisor. PROG (PARI) isok(n) = omega(n-1) == omega(n+1); \\ Michel Marcus, Oct 18 2016 CROSSREFS Cf. A063464. Sequence in context: A298809 A335194 A307647 * A175071 A336822 A140497 Adjacent sequences:  A088067 A088068 A088069 * A088071 A088072 A088073 KEYWORD nonn AUTHOR Amarnath Murthy, Sep 22 2003 EXTENSIONS More terms from Ray Chandler, Sep 27 2003 Offset corrected and formula adapted by Michel Marcus, Oct 18 2016 STATUS approved

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Last modified November 27 11:58 EST 2021. Contains 349385 sequences. (Running on oeis4.)