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 A097468 Number of 1's in the decimal expansion of the lesser of twin primes. 0
 0, 0, 2, 1, 0, 1, 0, 1, 2, 1, 1, 1, 1, 2, 1, 0, 0, 0, 1, 2, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 2, 2, 1, 2, 2, 3, 1, 1, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 0, 1, 0, 3, 1, 2, 0, 0, 0, 0, 1, 0, 1, 0, 0, 2, 0, 0, 1, 0, 0, 2, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,3 COMMENTS n=5000,d=1 in PARI code below. LINKS EXAMPLE 11 is the third lesser twin prime so 2 is the third entry MATHEMATICA DigitCount[#, 10, 1]&/@(Select[Partition[Prime[Range[1000]], 2, 1], #[[2]] - #[[1]] == 2&][[All, 1]]) (* Harvey P. Dale, Dec 24 2018 *) PROG (PARI) g(n, d) = forprime(x=1, n, if(isprime(x+2), print1(countchr(x, d)", "))) \Count the occurrences of char in string str countchr(str, char) = { local(ln, x, c); str=Str(str); \This allows leaving quotes off input char=Str(char); c=0; ln=length(str); for(x=1, ln, if(mid(str, x, 1)==char, c++); ); return(c) } \ Get a substring of length n from string str starting at position s in str. mid(str, s, n) = { local(v, ln, x, tmp); v =""; tmp = Vec(str); ln=length(tmp); for(x=s, s+n-1, v=concat(v, tmp[x]); ); return(v) } CROSSREFS Sequence in context: A271420 A099313 A316491 * A339975 A283144 A098381 Adjacent sequences:  A097465 A097466 A097467 * A097469 A097470 A097471 KEYWORD base,nonn AUTHOR Cino Hilliard, Aug 23 2004 STATUS approved

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Last modified June 18 14:29 EDT 2021. Contains 345114 sequences. (Running on oeis4.)