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A181920
Length of A185120(n): number of subsequent digits in the decimal expansion of e which form the next longer prime.
0
1, 2, 25, 90, 456, 608, 1421, 1469
OFFSET
1,2
COMMENTS
By definition, a strictly increasing sequence.
See A185120 for further comments and explanations.
EXAMPLE
The decimal expansion of e=exp(1)=2.718281828.... is split into
A185120(1) = 2 of length a(1)=1,
A185120(2) = 71 of length a(2)=2,
A185120(3) = 8281828459045235360287471 of length a(3)=25, etc.
PROG
(PARI) {default(realprecision, 2000); e=exp(1)*.1; for( n=1, 9e9, ispseudoprime(e\.1^n)|next; print1(n", "); e=frac(e*10^n))}
CROSSREFS
Sequence in context: A348064 A069232 A269232 * A123012 A175522 A226418
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Apr 01 2012
STATUS
approved