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A000190 Number of solutions to x^4 == 0 (mod n). 13
1, 1, 1, 2, 1, 1, 1, 4, 3, 1, 1, 2, 1, 1, 1, 8, 1, 3, 1, 2, 1, 1, 1, 4, 5, 1, 9, 2, 1, 1, 1, 8, 1, 1, 1, 6, 1, 1, 1, 4, 1, 1, 1, 2, 3, 1, 1, 8, 7, 5, 1, 2, 1, 9, 1, 4, 1, 1, 1, 2, 1, 1, 3, 16, 1, 1, 1, 2, 1, 1, 1, 12, 1, 1, 5, 2, 1, 1, 1, 8, 27, 1, 1, 2, 1, 1, 1, 4, 1, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Shadow transform of fourth powers A000583. - Michel Marcus, Jun 06 2013

LINKS

T. D. Noe, Table of n, a(n) for n = 1..10000

H. Bottomley, Some Smarandache-type multiplicative sequences

N. J. A. Sloane, Transforms

FORMULA

Multiplicative with a(p^e) = p^[3e/4]. - David W. Wilson, Aug 01 2001

MATHEMATICA

Array[ Function[ n, Count[ Array[ PowerMod[ #, 4, n ]&, n, 0 ], 0 ] ], 100 ]

PROG

(PARI) a(n)=my(f=factor(n)); prod(i=1, #f[, 1], f[i, 1]^(3*f[i, 2]\4)) \\ Charles R Greathouse IV, Jun 07 2013

CROSSREFS

Sequence in context: A125653 A104445 A000189 * A003557 A073752 A128708

Adjacent sequences:  A000187 A000188 A000189 * A000191 A000192 A000193

KEYWORD

nonn,mult

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified August 17 01:10 EDT 2017. Contains 290631 sequences.