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A308467
The smallest positive n-digit 4th power.
1
1, 16, 256, 1296, 10000, 104976, 1048576, 10556001, 100000000, 1003875856, 10098039121, 100469346961, 1000000000000, 10016218555281, 100091400875761, 1000417426149376, 10000000000000000, 100004631514837921, 1000028258199628641
OFFSET
1,2
FORMULA
a(n) = ceiling(10^((n-1)/4))^4. - Charlie Neder, Jun 13 2019
a(n) = A018074(n-1)^4. - Michel Marcus, Jun 13 2019
EXAMPLE
a(1) = 1^4 = 1;
a(2) = 2^4 = 16;
3^4 = 81 so no increase in number of digits;
a(3) = 4^4 = 256.
PROG
(Magma) sol:=[]; for k in [0..20] do if k mod 4 eq 0 then sol[k+1]:=10^k; else sol[k+1]:=(Floor(10^(k/4)) +1)^4; end if; end for; sol; // Marius A. Burtea, Jun 13 2019
CROSSREFS
Cf. A000583 (4th powers), A018074.
Sequence in context: A207750 A207126 A207947 * A223404 A263566 A208140
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
a(11)-a(19) from Charlie Neder, Jun 13 2019
STATUS
approved