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A074461 Average digit (rounded down) in the decimal expansion of the n-th prime number. 4
2, 3, 5, 7, 1, 2, 4, 5, 2, 5, 2, 5, 2, 3, 5, 4, 7, 3, 6, 4, 5, 8, 5, 8, 8, 0, 1, 2, 3, 1, 3, 1, 3, 4, 4, 2, 4, 3, 4, 3, 5, 3, 3, 4, 5, 6, 1, 2, 3, 4, 2, 4, 2, 2, 4, 3, 5, 3, 5, 3, 4, 4, 3, 1, 2, 3, 2, 4, 4, 5, 3, 5, 5, 4, 6, 4, 6, 6, 1, 4, 4, 2, 2, 3, 5, 3, 5, 5, 3, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A004426(A000040(n)). - Reinhard Zumkeller, May 27 2010

EXAMPLE

prime numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23, ... so the average digits rounded down are; 2, 3, 5, 7, (1+1)/2 = 1, (1+3)/2 = 2, (1+7)/2 = 4, (1+9)/2 = 5, floor((2+3)/2) = 2, ...

PROG

(PARI) a(n)={my(v=digits(prime(n))); vecsum(v)\#v} \\ Andrew Howroyd, Jan 16 2020

CROSSREFS

Cf. A000040, A004426, A074462.

Sequence in context: A065859 A258062 A117819 * A285095 A073342 A074462

Adjacent sequences:  A074458 A074459 A074460 * A074462 A074463 A074464

KEYWORD

easy,nonn,base

AUTHOR

Y. Kelly Itakura (yitkr(AT)mta.ca), Aug 23 2002

EXTENSIONS

Offset corrected and terms a(21) and beyond from Andrew Howroyd, Jan 16 2020

STATUS

approved

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Last modified September 20 23:04 EDT 2021. Contains 347596 sequences. (Running on oeis4.)