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A198190 Primes from the decimal expansion of sqrt(2), sorted first by the final digit index and then by length. 0
41, 2, 421, 3, 13, 5, 2, 3, 23, 5623, 135623, 42135623, 4142135623, 7, 37, 56237, 3, 73, 373, 3562373, 213562373, 7309, 37309, 5, 5048801, 414213562373095048801, 7, 887, 488016887, 142135623730950488016887, 2, 2, 688724209, 414213562373095048801688724209 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

The first digit, 1, is not prime.

The second digit, 4, cannot terminate any prime.

The third digit, 1, is not prime, but 41 is, so a(1) = 41. 141 is not prime, so it is not in the sequence.

PROG

(PARI) v=[1, 4, 1, 4, 2, 1, 3, 5, 6, 2, 3, 7, 3, 0, 9, 5, 0, 4, 8, 8, 0, 1, 6, 8, 8, 7, 2, 4, 2, 0, 9, 6, 9]

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. A002193.

Sequence in context: A283895 A051317 A036189 * A106424 A126636 A095188

Adjacent sequences:  A198187 A198188 A198189 * A198191 A198192 A198193

KEYWORD

nonn,base

AUTHOR

Franklin T. Adams-Watters, Oct 21 2011

STATUS

approved

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Last modified June 6 18:59 EDT 2020. Contains 334832 sequences. (Running on oeis4.)