

A169963


Number of (2n+1)digit squares in carryless arithmetic mod 10.


3



5, 46, 452, 4504, 45008, 450016, 4500032, 45000064, 450000128, 4500000256, 45000000512, 450000001024, 4500000002048, 45000000004096, 450000000008192, 4500000000016384, 45000000000032768, 450000000000065536, 4500000000000131072, 45000000000000262144
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OFFSET

0,1


LINKS

Table of n, a(n) for n=0..19.
David Applegate, Marc LeBrun and N. J. A. Sloane, Carryless Arithmetic (I): The Mod 10 Version.
Index entries for sequences related to carryless arithmetic
Index entries for linear recurrences with constant coefficients, signature (12,20).


FORMULA

For formula see Maple code.
a(n) = 12*a(n1)20*a(n2). G.f.: (14*x5) / ((2*x1)*(10*x1)).  Colin Barker, May 11 2013


MAPLE

f : n>2^((n1)/2) + add( 5^d*2^((n+1)/2), d=0..(n3)/2) + 2^((n+3)/2)*5^((n1)/2);


CROSSREFS

See A059729 for the actual squares.
Sequence in context: A096947 A042533 A309185 * A198256 A232972 A127304
Adjacent sequences: A169960 A169961 A169962 * A169964 A169965 A169966


KEYWORD

nonn,base,easy


AUTHOR

N. J. A. Sloane, Aug 07 2010


STATUS

approved



