A229155 -id:A229155 - cp's OEIS frontend

A229181 Number of decimal digits in the variant of A047777(n) (decimal expansion of Pi cut in "prime chunks") without the restriction that all primes must be different.

1, 5, 1, 3, 1, 2, 1, 4, 3057, 1, 1, 3, 1, 1, 748, 2, 2, 1, 2, 83, 5, 1, 2, 71, 10, 1, 1, 2, 2, 2, 1, 1, 3, 1, 14, 2, 5, 51, 1, 6, 1, 6, 3, 2, 9, 1, 16, 2, 3, 43, 1, 6, 19, 1, 5, 3, 1999, 1, 1, 2, 22, 1, 3, 1, 2, 2, 1, 2, 2, 5, 1, 1, 1, 1, 4, 1, 1, 3, 7, 5, 1, 6, 4, 3, 1, 10, 7, 1, 2, 11, 2, 5, 1, 13, 1, 20, 16, 1, 9, 16

Offset: 1

M. F. Hasler, Sep 15 2013

A variant of A121267. First differences of A053013. See these two sequences for further details.

C. Rivera, Prime strings

Cf. A047777, A053013, A121267, A229155.

A229181 = {1}; digits = Join[{{1}}, RealDigits[Pi, 10, 10^4] // First // Rest]; digits //. {a:({A229181,%20lg%5D;%20%7B%7B1%7D,%20c%7D)%20;%20A229181%20(*%20_Jean-Fran%C3%A7ois%20Alcover">Integer..}..), b__Integer /; PrimeQ[FromDigits[{b}]], c___Integer} :> (Print[lg = {b} // Length]; AppendTo[A229181, lg]; {{1}, c}) ; A229181 (* _Jean-François Alcover, Oct 17 2013 *)

default(realprecision,5000);c=Pi/10;u=[];for(k=1,9e9,ispseudoprime(c\.1^k) & !print1(k,",") & k=0*c=frac(c*10^k))

More terms from Jean-François Alcover, Oct 17 2013

A229178 Primes seen in decimal expansion of e, contiguous, smallest and distinct, with terms larger than 10^100 replaced by 0.

Original entry on oeis.org

2, 7, 0, 5, 3, 11, 80232878250981945581530175671, 73, 61, 332069, 811, 2509961, 81881593, 41, 0, 30592123, 66771943252786753, 0, 0, 6343, 490769, 64237, 2229435236612557250881, 47, 79, 223, 151, 97, 477806056967, 253801, 71, 0, 0, 9467, 83, 48197

Offset: 1

M. F. Hasler, Sep 15 2013

Sequence A047777 is the analog for Pi.

Without the admittedly arbitrary clause "terms larger than ... replaced by zero", the sequence could not be stored beyond its second term, since the 3rd term would have 649 digits (and the 15th term would have 441 digits). Although this restriction is arbitrary, several other (maybe more natural) alternatives (for example, larger than the concatenation of the preceding/following 10 terms...) would yield the same initial terms.

Cf. A001113, A007512, A047777, A064118, A229155.

default(realprecision,5000);c=exp(1)/10;u=[];for(k=0,9e9,ispseudoprime(c\.1^k) & !setsearch(u,c\.1^k) & (u=setunion(u,Set(c\.1^k))) & !print1(c\.1^k,",") & k=0*c=frac(c*10^k))

More terms from Jinyuan Wang, Mar 26 2020

cp's OEIS Frontend

A229181 Number of decimal digits in the variant of A047777(n) (decimal expansion of Pi cut in "prime chunks") without the restriction that all primes must be different.

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