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A163984 First differences of A056737. 0
1, 1, -2, 4, -3, 5, -4, -2, 3, 7, -9, 11, -7, -3, -2, 16, -13, 15, -17, 3, 5, 13, -20, -2, 11, -5, -3, 25, -27, 29, -26, 4, 7, -13, -2, 36, -19, -7, -7, 37, -39, 41, -35, -3, 17, 25, -44, -2, 5, 9, -5, 43, -49, 3, -5, 15, 11, 31, -54, 56, -31, -27, -2, 8, -3, 61, -53, 7, -17, 67, -69, 71, -37, -25, 5, -11, 3, 71, -76, -2, 39, 43, -77, 7, 29, -15 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..86.

Omar E. Pol, Illustration: Divisors and pi(x)

MAPLE

A033676 := proc(n) local a, d; a := 0 ; for d in numtheory[divisors](n) do if d^2 <= n then a := max(a, d) ; fi; od: a; end:

A033677 := proc(n) local a, d; a := n ; for d in numtheory[divisors](n) do if d^2 >= n then a := min(a, d) ; fi; od: a; end proc:

A056737 := proc(n) A033677(n)-A033676(n) ; end proc:

[seq(A056737(n), n=1..120)] ;

DIFF(%) ;

CROSSREFS

Cf. A033676, A033677, A056737, A147861, A163100, A163280, A163990.

Sequence in context: A249484 A134017 A292285 * A283366 A048186 A060762

Adjacent sequences:  A163981 A163982 A163983 * A163985 A163986 A163987

KEYWORD

easy,sign

AUTHOR

Omar E. Pol, Aug 12 2009

STATUS

approved

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Last modified August 1 03:52 EDT 2021. Contains 346384 sequences. (Running on oeis4.)