A325175 - OEIS

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A325175

Numbers k such that s(k) = s(k+1) = s(k+2) = s(k+3) where s(k) is the sum of divisors of k that are smaller than sqrt(k) (A070039).

2, 1190499411, 7896840789, 9190223334, 10546199943, 13239147654, 16488284454, 19818736503, 19927041063, 20401914903, 20551875063, 24219563814, 25442242503, 27391724583, 34539825543, 35714513463, 37014168183, 44120613543, 44130940614, 44514172134, 48647900639

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OFFSET

1,1

COMMENTS

Five consecutive coincident values of A070039 are also possible. One such occurrence starts a 211301122224870.

LINKS

Table of n, a(n) for n=1..21.

EXAMPLE

2 is in the sequence since A070039(2) = A070039(3) = A070039(4) = A070039(5) = 1.

CROSSREFS

Cf. A070039, A324295, A324310.

Sequence in context: A170999 A249482 A214600 * A306499 A051241 A094486

Adjacent sequences: A325172 A325173 A325174 * A325176 A325177 A325178

KEYWORD

nonn

AUTHOR

Giovanni Resta, Sep 05 2019

STATUS

approved