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A332386 Numbers k such that k and k + 1 have the same number of divisors in Eisenstein integers. 3
3, 7, 32, 50, 68, 174, 184, 200, 212, 219, 247, 291, 328, 343, 368, 376, 435, 472, 495, 543, 579, 608, 644, 679, 712, 716, 723, 788, 795, 849, 860, 871, 874, 904, 932, 939, 1011, 1015, 1058, 1074, 1076, 1159, 1184, 1220, 1227, 1336, 1359, 1384, 1436, 1495, 1515 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

3 is a term since 3 and 4 both have 3 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]; SequencePosition[eisNumDiv /@ Range[1520], {x_, x_}][[All, 1]] (* after Harvey P. Dale at A005237 *)

CROSSREFS

Cf. A005237, A319442, A332312, A332387, A332388.

Sequence in context: A167917 A249761 A163081 * A096239 A074699 A115088

Adjacent sequences:  A332383 A332384 A332385 * A332387 A332388 A332389

KEYWORD

nonn

AUTHOR

Amiram Eldar, Feb 10 2020

STATUS

approved

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Last modified September 21 21:32 EDT 2021. Contains 347605 sequences. (Running on oeis4.)