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A087429 a(n) = if gpf(n) < gpf(n+1) then 1 else 0, where gpf=A006530 (greatest prime factor). 2
1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Equivalently, a(n) = 1 iff A061395(n+1) > A061395(n), otherwise a(n) = 0. - Giovanni Teofilatto, Jan 03 2008

a(n) = A057427(1+A057427(A070221(n)));

for primes p: a(p-1)=1 and a(p)=0;

a(A070089(n)) = 1, a(A070087(n)) = 0, a(A087430(n)) = 0.

LINKS

Table of n, a(n) for n=1..102.

MATHEMATICA

Join[{1}, Table[If[PrimePi[FactorInteger[n + 1][[ -1, 1]]] > PrimePi[FactorInteger[n][[ -1, 1]]], 1, 0], {n, 2, 90}]] (* Stefan Steinerberger, Jan 06 2008 *)

CROSSREFS

Cf. A061395.

Sequence in context: A331168 A331281 A105470 * A093075 A104120 A254634

Adjacent sequences:  A087426 A087427 A087428 * A087430 A087431 A087432

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 02 2003

EXTENSIONS

Edited by N. J. A. Sloane, Jul 01 2008, at the suggestion of R. J. Mathar

STATUS

approved

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Last modified July 11 23:53 EDT 2020. Contains 335654 sequences. (Running on oeis4.)