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A178919 Smallest of three consecutive integers divisible respectively by three consecutive squares greater than 1. 0
2223, 5823, 9423, 13023, 16623, 20223, 23823, 27423, 31023, 32975, 34623, 38223, 41823, 45423, 49023, 52623, 56223, 59823, 63423, 67023, 70623, 74223, 77075, 77823, 81423, 85023, 88623, 92223, 95823, 99423, 103023, 106623, 110223 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..33.

EXAMPLE

5823 is a term as 5823, 5824 and 5825 are divisible by 9, 16 and 25 respectively.

MAPLE

with(numtheory):for n from 1 to 200000 do: k:=0:q:=floor(sqrt(n)):for m from

  2 to q do: p1:=m^2:p2:=(m+1)^2:p3:=(m+2)^2:if irem(n, p1)=0 and irem(n+1, p2)=0

  and irem(n+2, p3)=0 and k=0 then k:=1:printf(`%d, `, n):else fi:od:od:

PROG

(Sage) is_A178919 = lambda n: any(all(((k+x)**2).divides(n+x) for x in range(3)) for k in divisors(n) if k > 1) # [D. S. McNeil, Dec 29 2010]

CROSSREFS

Cf. A178918

Sequence in context: A043500 A118116 A053395 * A205225 A236496 A208181

Adjacent sequences:  A178916 A178917 A178918 * A178920 A178921 A178922

KEYWORD

nonn

AUTHOR

Michel Lagneau, Dec 29 2010

STATUS

approved

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Last modified August 17 06:56 EDT 2018. Contains 313810 sequences. (Running on oeis4.)