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A085252 Number of ways to write n as sum of two powerful numbers (A001694). 6
0, 1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 2, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 2, 1, 1, 2, 1, 0, 0, 2, 2, 0, 1, 1, 1, 0, 0, 1, 0, 2, 0, 2, 1, 1, 0, 0, 2, 1, 1, 0, 1, 0, 1, 1, 2, 0, 0, 2, 0, 0, 0, 2, 2, 1, 0, 2, 0, 0, 0, 2, 2, 1, 0, 0, 2, 0, 0, 1, 2, 1, 1, 0, 0, 0, 0, 1, 2, 1, 1, 1, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,17

COMMENTS

a(A085253(n))=0; a(A076871(n))>0; a(A085254(n))=1; a(A085255(n))>1.

LINKS

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

Eric Weisstein's World of Mathematics, Powerful Number

EXAMPLE

a(81)=2: 81 = 9+72=A001694(4)+A001694(12) =

32+49=A001694(8)+A001694(10).

CROSSREFS

Sequence in context: A061007 A060838 A206567 * A250214 A073423 A219180

Adjacent sequences:  A085249 A085250 A085251 * A085253 A085254 A085255

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Jun 23 2003

STATUS

approved

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Last modified January 17 12:18 EST 2020. Contains 330958 sequences. (Running on oeis4.)