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A118129 Numbers n such that the sum of the first n odd composites is palindromic in base 3. 0
6, 14, 20, 424, 1042, 8290, 20802, 21644, 440512, 548008, 749171, 4366390, 5378548, 9850174, 17930596, 36158854, 130427194, 407305710 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No more terms through 10^9.

LINKS

Table of n, a(n) for n=1..18.

EXAMPLE

The sum of the first 14 odd composites, when written in base 3, is the palindrome 201102, so 14 is in the sequence.

CROSSREFS

Cf. A058848 (palindromic in base 10).

Sequence in context: A236928 A064708 A064709 * A046712 A162823 A020171

Adjacent sequences:  A118126 A118127 A118128 * A118130 A118131 A118132

KEYWORD

more,nonn,base

AUTHOR

Ryan Propper, May 12 2006

STATUS

approved

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Last modified December 8 20:37 EST 2021. Contains 349596 sequences. (Running on oeis4.)