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A359748
Numbers k such that k and k+1 are both in A359747.
2
3, 7, 71, 107, 242, 431, 1151, 2591, 3887, 21599, 49391, 76831, 79999, 107647, 139967, 179999, 197567, 268911, 345599, 346111, 401407, 438047, 472391, 995327, 1031047, 1143071, 1249999, 1254527, 1349999, 1438207, 1685447, 2056751, 2411207, 2829887, 3269807, 4464071
OFFSET
1,1
COMMENTS
Are there 3 terms in A359747 that are consecutive integers?
LINKS
EXAMPLE
7 is a term since 7*8 = 56 = 2^3 * 3^1 has 2 distinct exponents in its prime factorization (1 and 3) and 8*9 = 72 = 2^3 * 3^2 also has 2 distinct exponents in its prime factorization (2 and 3).
MATHEMATICA
q[n_] := UnsameQ @@ (FactorInteger[n*(n+1)][[;; , 2]]); Select[Range[10^5], q[#] && q[#+1] &]
PROG
(PARI) is(n) = { my(e1 = factor(n*(n+1))[, 2], e2 = factor((n+1)*(n+2))[, 2]); #Set(e1) == #e1 && #Set(e2) == #e2; }
CROSSREFS
Subsequence of A130091, A342028, A342029 and A359748.
Sequence in context: A127177 A261136 A127179 * A113841 A128072 A094008
KEYWORD
nonn
AUTHOR
Amiram Eldar, Jan 13 2023
STATUS
approved