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 A104202 Differences of straddle primes. 0
 2, 2, 4, 4, 4, 2, 4, 4, 4, 2, 4, 4, 4, 6, 6, 6, 6, 6, 2, 6, 6, 6, 6, 6, 4, 4, 4, 2, 4, 4, 4, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 2, 6, 6, 6, 6, 6, 4, 4, 4, 2, 6, 6, 6, 6, 6, 4, 4, 4, 6, 6, 6, 6, 6, 8, 8, 8, 8, 8, 8, 8, 4, 4, 4, 2, 4, 4, 4, 2, 4, 4, 4, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 14, 4, 4, 4, 6 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,1 LINKS FORMULA Straddle primes are the nearest primes preceding and following composite n. EXAMPLE The first straddle prime pair is 3 and 5 which straddles the composite number 4 and 5-3 = 2 the first entry in the table. MATHEMATICA NextPrime[#]-NextPrime[#, -1]&/@Rest[Select[Range[200], !PrimeQ[#]&]] (* Harvey P. Dale, Aug 23 2012 *) PROG (PARI) straddiff(n) = { local (x, y, pp, np); for(x=1, n, y=composite(x); pp=precprime(y); np=nextprime(y); print1(np-pp", ") ) composite(n) = { local(c, x); c=1; x=1; while(c <= n, x++; if(!isprime(x), c++); ); return(x) } } CROSSREFS Sequence in context: A006460 A064137 A329588 * A042946 A037202 A227091 Adjacent sequences:  A104199 A104200 A104201 * A104203 A104204 A104205 KEYWORD easy,nonn AUTHOR Cino Hilliard, Mar 13 2005 STATUS approved

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Last modified September 20 06:51 EDT 2020. Contains 337264 sequences. (Running on oeis4.)