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A088180
a(n) is the number of numbers m < 10^n for which there is at least one k such that k + reverse(k) = m.
1
1, 5, 19, 112, 368, 2161, 7033, 41140, 133730, 781884, 2541197, 14856466, 48283738, 282274893, 917394087, 5363229225, 17430497086, 101901374524, 331179473681, 1936126175213, 6292410089388, 36786397511512, 119555791973835, 698941553280624, 2271560048351176
OFFSET
0,2
COMMENTS
Number of terms of A067030 below 10^n.
a(16)-a(18) are based on two empirically detected recursive formulas. [Lars Blomberg, Nov 25 2011]
EXAMPLE
a(1) = 5 since 0, 2, 4, 6, 8 are the terms of A067030 which are smaller than 10^1.
CROSSREFS
Cf. A067030.
Sequence in context: A280067 A158615 A321652 * A370459 A206709 A199480
KEYWORD
nonn,base
AUTHOR
Klaus Brockhaus, Sep 22 2003
EXTENSIONS
a(9)-a(10) from Donovan Johnson, Sep 22 2009
a(11)-a(18) from Lars Blomberg, Dec 19 2011
a(19)-a(24) from Hiroaki Yamanouchi, Sep 04 2014
STATUS
approved