A110777 - OEIS

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A110777

Number of digits in A110776(n).

2, 3, 2, 6, 9, 25, 9, 3, 762, 354, 248, 2181, 606, 1941, 6423, 11871

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..16.

PROG

(Python)

from sympy import isprime

from itertools import count, islice

def agen(): # generator of terms

s = ""

while True:

for d in "17":

for k in count(1):

if isprime(int(s+d*k)): break

yield k

s += d*k

print(list(islice(agen(), 11))) # Michael S. Branicky, Aug 23 2022

CROSSREFS

Cf. A110774, A110775, A110776, A110778, A112534, A110780, A110781, A110782, A110783, A110788, A110789

Sequence in context: A158279 A153984 A025502 * A087454 A059446 A298854

Adjacent sequences: A110774 A110775 A110776 * A110778 A110779 A110780

KEYWORD

base,nonn,more

AUTHOR

Amarnath Murthy, Aug 12 2005

EXTENSIONS

a(7)-a(9) from Joshua Zucker, Jan 11 2006

a(10)-a(11) from Sean A. Irvine, Mar 22 2010

a(12)-a(14) from Michael S. Branicky, Aug 23 2022

a(15) from Michael S. Branicky, May 29 2023

a(16) from Michael S. Branicky, Nov 20 2024

STATUS

approved