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A247987
Numbers k such that A247985(k+1) - A247985(k) = 3.
3
1, 3, 4, 6, 7, 8, 10, 11, 12, 14, 15, 17, 18, 19, 21, 22, 24, 25, 26, 28, 29, 31, 32, 33, 35, 36, 38, 39, 40, 42, 43, 45, 46, 47, 49, 50, 51, 53, 54, 56, 57, 58, 60, 61, 63, 64, 65, 67, 68, 70, 71, 72, 74, 75, 77, 78, 79, 81, 82, 83, 85, 86, 88, 89, 90, 92
OFFSET
1,2
COMMENTS
Complement of A247986.
LINKS
MATHEMATICA
z = 100; p[k_] := p[k] = Product[(k^2 + h)/(k^2 - h), {h, 1, k}] (* Finch p. 14 *)
N[Table[p[n] - E, {n, 2, z}]]
f[n_] := f[n] = Select[1 + Range[z], p[#] - E < 1/n &, 1];
u = Flatten[Table[f[n], {n, 1, z}]] ; (* A247985 *)
v = Differences[u];
Flatten[Position[v, 2]]; (* A247986 *)
Flatten[Position[v, 3]]; (* A247987 *)
CROSSREFS
Sequence in context: A234349 A042954 A361457 * A062975 A276218 A047299
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Sep 29 2014
STATUS
approved