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A260262
Number of digits of hyperfactorial(hyperfactorial(n)).
2
1, 1, 5, 10703, 1614696745, 28812381422477890, 100652205682053466439353073, 100862590668529143951825397261798321446, 39596172587764149886638486692811308322476202830248047, 7942534398808419809836601901425429825855063583537701822391757140131840
OFFSET
0,3
LINKS
FORMULA
a(n) = floor(log_10(hyperfactorial(hyperfactorial(n))))+1.
a(n) = A055642(A002109(A002109(n))).
EXAMPLE
Hyperfactorial(Hyperfactorial(1)) = 1. There is 1 digit in the number 1. Because of this, a(1) = 1.
MATHEMATICA
Table[Floor[Log[10, Hyperfactorial[Hyperfactorial[n]]]] + 1, {n, 0, 3}]
PROG
(PARI) hyperfactorial(n)=prod(k=2, n, k^k)
first(m)=vector(m, i, #digits(hyperfactorial(hyperfactorial(i)))) \\ Anders Hellström, Aug 29 2015
CROSSREFS
Sequence in context: A101846 A292742 A376103 * A058051 A242772 A368067
KEYWORD
nonn,easy,base
AUTHOR
Matthew Campbell, Jul 21 2015
STATUS
approved