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A261175 Number of digits of Hyperfactorial(n). 1
1, 1, 1, 3, 5, 8, 13, 19, 26, 35, 45, 56, 69, 84, 100, 117, 137, 158, 180, 204, 231, 258, 288, 319, 352, 387, 424, 463, 503, 546, 590, 636, 684, 734, 786, 840, 897, 955, 1015, 1077, 1141, 1207, 1275, 1345, 1418, 1492, 1568, 1647, 1728, 1811, 1896, 1983, 2072, 2163, 2257, 2352 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Chai Wah Wu, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = 1 + floor( log_10( A002109(n))) = A055642(A002109(n)).

MATHEMATICA

Table[1 + Floor@ Log10@ Hyperfactorial@ n, {n, 0, 55}]

PROG

(PARI) a(n)=my(r=1); for(i=1, n+1, r *= i^i); floor(log(r)/log(10))+1 \\ Anders Hellström, Aug 20 2015

(PARI) vector(60, n, n--; #Str(prod(k=2, n, k^k))) \\ Michel Marcus, Aug 20 2015

(Python)

A261175_list, n = [], 1

for i in range(100):

    n *= i**i

A261175_list.append(len(str(n)))  # Chai Wah Wu, Aug 21 2015

CROSSREFS

Cf. A002109, A061010, A260262.

Sequence in context: A175388 A310037 A104563 * A265064 A030762 A023500

Adjacent sequences:  A261172 A261173 A261174 * A261176 A261177 A261178

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Aug 20 2015

STATUS

approved

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Last modified September 20 01:54 EDT 2020. Contains 337260 sequences. (Running on oeis4.)