A093337 Penultimate digits of the primes.
1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 4, 5, 5, 6, 6, 7, 7, 7, 8, 8, 9, 0, 0, 0, 0, 1, 2, 3, 3, 3, 4, 5, 5, 6, 6, 7, 7, 8, 9, 9, 9, 9, 1, 2, 2, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 0, 1, 1, 1, 3, 3, 4, 4, 5, 5, 6, 7, 7, 8, 8, 9, 0, 0, 1, 2, 3, 3, 3, 4, 4, 5, 6, 6, 6, 7, 8, 9, 9, 0, 0, 2, 2, 4, 4, 5, 6, 6, 7, 7, 8, 9, 9
Offset: 11
Programs
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Magma
[Intseq(p)[2]: p in PrimesInInterval(11,600)]; // Bruno Berselli, Feb 14 2013
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Mathematica
IntegerDigits[#][[-2]]&/@Prime[Range[5,110]] (* Harvey P. Dale, Apr 08 2019 *)
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PARI
penult(n) = { forprime(x=11,n, s = Str(x); ln = length(s); pu = mid(s,ln-1,1); print1(pu",") ) } \ Get a substring of length n from string str starting at position s in str. mid(str,s,n) = { v =""; tmp = Vec(str); ln=length(tmp); for(x=s,s+n-1, v=concat(v,tmp[x]); ); return(v) }