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A144563 Subset of A020342 (vampire numbers, definition 1) listing numbers which have more than one such representation of the desired form. 6
1260, 1395, 1530, 6880, 12060, 12550, 12600, 13950, 14350, 15030, 15300, 18270, 21870, 31590, 37840 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

1260 = 21*60 = 6*210. 1395 = 5*9*31 = 15*93. 1530 = 30*51 = 3*510.

CROSSREFS

Closely related: A020342, A014575, A080718, A280928, A048936.

Sequence in context: A099592 A240922 A014575 * A175746 A291714 A179690

Adjacent sequences:  A144560 A144561 A144562 * A144564 A144565 A144566

KEYWORD

nonn,base,more

AUTHOR

N. J. A. Sloane, Jan 03 2009, based on email from Zak Seidov

EXTENSIONS

Corrected A-number in definition. More terms and examples R. J. Mathar, Jan 05 2009

STATUS

approved

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Last modified November 18 05:08 EST 2017. Contains 294853 sequences.