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A371390
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Numbers k such that prime(k), prime(k+1), prime(k+2), prime(k+3) and prime(k+4) all have the same last digit.
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2
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11582, 17385, 19317, 20579, 22931, 42098, 51895, 52252, 55259, 60393, 62192, 62193, 62680, 64050, 65324, 71483, 76391, 76773, 76805, 77052, 81139, 86711, 95661, 100208, 102032, 113646, 113892, 113954, 115251, 124227, 125218, 125586, 144165, 144299, 147619, 147620
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OFFSET
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1,1
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LINKS
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EXAMPLE
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11582 is a term because prime(11582) = 123229, prime(11583) = 123239, prime(11584) = 123259, prime(11585) = 123269 with the same last digit 9.
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MAPLE
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nn:=15*10^4:d:=array(1..5):
for n from 1 to nn do:
for k from 1 to 5 do:
d[k]:=irem(ithprime(n+k-1), 10):
od:
if d[1]=d[2] and d[1]=d[3] and
d[1]=d[4] and d[1]=d[5]
then
printf(`%d, `, n):
else
fi:
od:
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PROG
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(PARI) \\ See PARI link
(Python)
from itertools import count, islice
from sympy import nextprime
def A371390_gen(): # generator of terms
xlist, p = [2, 3, 5, 7, 1], 11
for k in count(1):
if len(set(xlist)) == 1:
yield k
p = nextprime(p)
xlist = xlist[1:]+[p%10]
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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