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A332387 Numbers k such that k, k + 1 and k + 2 have the same number of divisors in Eisenstein integers. 3
13448, 27848, 75774, 135400, 243338, 276123, 396950, 452823, 497575, 524823, 565674, 587575, 632224, 639848, 719223, 769316, 861123, 935799, 1060904, 1073875, 1153023, 1204312, 1308856, 1366624, 1413498, 1490599, 1555975, 1565223, 1601798, 1767424, 1902774, 1923295 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

13448 is a term since 13448, 13449 and 13450 each have 12 divisors in Eisenstein integers.

MATHEMATICA

f[p_, e_] := Switch[Mod[p, 3], 0, 2*e + 1, 1, (e + 1)^2, 2, e + 1]; eisNumDiv[1] = 1; eisNumDiv[n_] := Times @@ f @@@ FactorInteger[n]; Flatten[Position[Partition[ eisNumDiv /@ Range[10^6], 3, 1], {x_, x_, x_}]] (* after Harvey P. Dale at A005238 *)

CROSSREFS

Cf. A005238, A319442, A332313, A332386, A332388.

Sequence in context: A157506 A238176 A035917 * A183676 A204394 A250818

Adjacent sequences:  A332384 A332385 A332386 * A332388 A332389 A332390

KEYWORD

nonn

AUTHOR

Amiram Eldar, Feb 10 2020

STATUS

approved

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Last modified January 28 23:12 EST 2022. Contains 350670 sequences. (Running on oeis4.)