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A238713
Least member of decadal prime triples: First prime beyond 10*A008470(n).
5
11, 41, 71, 101, 131, 191, 223, 311, 431, 461, 613, 641, 821, 853, 881, 1031, 1061, 1091, 1301, 1423, 1451, 1481, 1601, 1663, 1693, 1783, 1871, 1993, 2081, 2381, 2683, 2711, 3163, 3251, 3461, 3671, 3761, 3911, 4001, 4091, 4153, 4211, 4513, 4721, 4783, 4931
OFFSET
1,1
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
a(n) = nextprime(10*A008470(n)).
PROG
(PARI) for(d=1, 999, primepi(10*(d+1))-primepi(10*d) >2|next; print1(nextprime(d*10+1)", "))
(PARI) is(n)=my(t=n%10); if(t==1, isprime(n) && if(isprime(n+2), isprime(n+6) || isprime(n+8), isprime(n+6) && isprime(n+8)), t==3 && isprime(n) && !isprime(n-2) && isprime(n+4) && isprime(n+6)) \\ Charles R Greathouse IV, Mar 04 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Mar 03 2014
STATUS
approved