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A332842 Initial digit of n-th superfactorial. 1
1, 1, 2, 1, 2, 3, 2, 1, 5, 1, 6, 2, 1, 7, 6, 9, 1, 6, 4, 5, 1, 6, 7, 1, 1, 1, 7, 7, 2, 2, 5, 4, 1, 1, 3, 3, 1, 1, 8, 1, 1, 4, 6, 4, 1, 1, 7, 1, 2, 1, 4, 6, 5, 2, 5, 6, 4, 1, 4, 6, 5, 2, 8, 1, 2, 1, 9, 3, 8, 1, 1, 1, 9, 4, 1, 3, 6, 9, 1, 9, 6, 3, 1, 7, 2, 6, 1, 3, 6, 1, 1, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Chai Wah Wu, Table of n, a(n) for n = 0..10000

FORMULA

a(n) = A000030(A000178(n)).

EXAMPLE

a(6) = 2 because A000178(6) = 24883200.

PROG

(PARI) a(n) = digits(prod(k=2, n, k!))[1]; \\ Michel Marcus, Feb 26 2020

(Python)

def A332842(n):

    m, k = 1, 1

    for i in range(2, n+1):

        k *= i

        m *= k

    return int(str(m)[0]) # Chai Wah Wu, Mar 17 2020

CROSSREFS

Cf. A000030, A000178, A008905.

Sequence in context: A336157 A190167 A339010 * A171565 A328266 A115116

Adjacent sequences:  A332839 A332840 A332841 * A332843 A332844 A332845

KEYWORD

easy,nonn,base

AUTHOR

Eder Vanzei, Feb 26 2020

STATUS

approved

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Last modified June 12 08:13 EDT 2021. Contains 344943 sequences. (Running on oeis4.)