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A102354 a(n) is the number of ways n can be written as k^2 * j, 0 < j <= k. 8
1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,64

COMMENTS

Sum_{n>0} a(n)/n = 2*zeta(3). See A152648.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

a(n) >= A102448(n). - Antti Karttunen, Aug 27 2017

EXAMPLE

a(18) = 1 because 18 = k^2 * j, j <= k, in one way: k=3, j=2.

MATHEMATICA

t = Sort[ Flatten[ Table[k^2*j, {k, 11}, {j, k}]]]; Table[ Count[t, n], {n, 105}] (* Robert G. Wilson v, Feb 22 2005 *)

PROG

(PARI) A102354(n) = sumdiv(n, d, (issquare(d) && (sqrtint(d) >= (n/d)))); \\ Antti Karttunen, Aug 27 2017

CROSSREFS

Cf. A102448, A104020, A104022, A104024, A152648.

Sequence in context: A323913 A014082 A322583 * A157228 A193138 A255320

Adjacent sequences:  A102351 A102352 A102353 * A102355 A102356 A102357

KEYWORD

nonn

AUTHOR

Leroy Quet, Feb 21 2005

EXTENSIONS

More terms from Robert G. Wilson v, Feb 22 2005

STATUS

approved

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Last modified October 17 18:58 EDT 2019. Contains 328127 sequences. (Running on oeis4.)