

A332315


Numbers k such that k and k + 1 have the same norm of the sum of divisors in Gaussian integers.


1



30514, 36777, 43978, 3474262, 5745125, 10628554, 16567494, 40831527, 58008301, 111798477, 142981839, 288834504, 392413941, 580867202, 650141557, 944224497, 967593411, 1874210882, 6306287377, 6442064745, 7377567197, 8121464245
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OFFSET

1,1


COMMENTS

The first term, 30514, is also a number k such that k and k + 1 have the sum divisors in Gaussian integers: 54720 + 48960*i (where i is the imaginary unit). What is the next term with this property?
No more terms below 1.5*10^10.


LINKS

Table of n, a(n) for n=1..22.


EXAMPLE

30514 is a term since A103230(30514) = A103230(30515) = 5391360000.


MATHEMATICA

csigma[n_] :=(Abs @ DivisorSigma[1, n, GaussianIntegers > True])^2; seq = {}; n1 = csigma[1]; Do[n2 = csigma[n]; If[n1 == n2, AppendTo[seq, n  1]]; n1 = n2, {n, 2, 5*10^5}]; seq


CROSSREFS

Cf. A002961, A064125, A103228, A103229, A103230, A293183, A306985.
Sequence in context: A251527 A226528 A278271 * A254976 A234791 A134118
Adjacent sequences: A332312 A332313 A332314 * A332316 A332317 A332318


KEYWORD

nonn,more


AUTHOR

Amiram Eldar, Feb 09 2020


STATUS

approved



