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 A243200 Let A242720(n)-3 = prime(l)*prime(m), l<=m; a(n)=m-l. 0
 0, 1, 1, 3, 1, 1, 1, 3, 4, 4, 3, 2, 2, 6, 6, 5, 1, 1, 5, 2, 2, 2, 10, 5, 5, 3, 3, 3, 2, 2, 2, 1, 1, 1, 3, 2, 2, 5, 1, 1, 3, 3, 3, 3, 6, 7, 4, 1, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 3, 3, 3, 1, 1, 1, 2, 2, 2, 2, 2, 2, 8, 6, 6, 6, 1, 1, 1, 1, 1, 1, 7, 1, 1, 1, 4, 2, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,4 COMMENTS Since for a prime p>3, p^2 == 1 (mod 3), then for n>2, A242720(n) is not equal to p^2 + 3 (otherwise, lpf(A242720(n) - 1) = 3). So, the sequence has only zero term a(2). LINKS CROSSREFS Cf. A242720, A242719, A243154, A243158. Sequence in context: A295295 A069290 A076476 * A016733 A060234 A131270 Adjacent sequences:  A243197 A243198 A243199 * A243201 A243202 A243203 KEYWORD nonn AUTHOR Vladimir Shevelev, Jun 01 2014 EXTENSIONS More terms from Peter J. C. Moses, Jun 01 2014 STATUS approved

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Last modified May 12 13:46 EDT 2021. Contains 343823 sequences. (Running on oeis4.)