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A067042 Numbers in which the product of digits in even positions = product of digits in odd positions. 1
11, 22, 33, 44, 55, 66, 77, 88, 99, 100, 111, 122, 133, 144, 155, 166, 177, 188, 199, 200, 221, 242, 263, 284, 300, 331, 362, 393, 400, 441, 482, 500, 551, 600, 661, 700, 771, 800, 881, 900, 991, 1000, 1001, 1002, 1003, 1004, 1005, 1006, 1007, 1008, 1009 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

FORMULA

Asymptotics: For any n, let f(n) be the number of entries in this sequence that are less than n. Then f(n)/n approaches 1 as n goes to infinity. This is because among numbers with a large number of digits, almost all have 0's in both odd positions and even positions. - David Wasserman, Jan 16 2002

EXAMPLE

2364 is a member as 2*6 = 3*4.

CROSSREFS

Sequence in context: A160861 A302575 A302801 * A078273 A345391 A065571

Adjacent sequences:  A067039 A067040 A067041 * A067043 A067044 A067045

KEYWORD

base,nonn,easy

AUTHOR

Amarnath Murthy, Dec 29 2001

EXTENSIONS

Corrected by David Wasserman, Jan 16 2002

More terms from Sascha Kurz, Mar 23 2002

STATUS

approved

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Last modified October 26 00:52 EDT 2021. Contains 348256 sequences. (Running on oeis4.)