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A198187 Primes from the decimal expansion of Pi, sorted first by the final digit index and then by length. 3
3, 31, 41, 5, 59, 4159, 14159, 314159, 2, 5, 3, 53, 653, 1592653, 5, 89, 141592653589, 7, 97, 5897, 35897, 6535897, 5926535897, 415926535897, 79, 58979, 358979, 3, 589793, 2, 3, 23, 9323, 9265358979323, 2, 3, 43, 643, 462643, 93238462643, 3, 433, 3, 83, 383 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

In this sequence, primes are listed each time they occur (again) with a new ending position, in contrast to A198019 where only the first occurrence of each prime is listed. - M. F. Hasler, Sep 02 2013

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

The first digit is 3, which is prime, so a(1) = 3.

The second digit is 1, which is no prime, but 31 is prime, so a(2) = 31.

The third digit is 4, which does not end any prime.

The fourth digit is 1, not prime, but 41 is prime, so a(3) = 41.

PROG

(PARI) v=[3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5, 8, 9, 7, 9, 3, 2, 3, 8, 4, 6, 2, 6, 4, 3, 3, 8, 3]

for(n=1, #v, x=0; p=1; forstep(k=n, 1, -1, x+=p*v[k]; p*=10; if(v[k]&&isprime(x), print1(x", "))))

CROSSREFS

Cf. A104841.

Cf. A198018, A198019, A195834, A005042, A047777, A053013, A064467.

Sequence in context: A046282 A045709 A090151 * A198019 A198018 A211003

Adjacent sequences:  A198184 A198185 A198186 * A198188 A198189 A198190

KEYWORD

nonn,base

AUTHOR

Franklin T. Adams-Watters, Oct 21 2011

STATUS

approved

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Last modified May 26 05:18 EDT 2017. Contains 287074 sequences.