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A088062
a(1) = 2; thereafter a(n) = smallest number of copies of (the decimal expansion of) n that are needed to prefix A088061(n-1) with in order to get a prime (the prime being A088061(n)).
1
2, 1, 2, 3, 2, 1, 12, 634, 623
OFFSET
1,1
EXAMPLE
a(4) = 3, A088061(3) = 33211 and A088061(4) = 44433211.
PROG
(PARI) x=0; n=-1; for(k=1, 9, z=n; while(1, n++; x=x+k*10^n; if(ispseudoprime(x), print(z=n-z); break))) \\ Dmitry Petukhov, Oct 15 2017
CROSSREFS
Cf. A088061.
Sequence in context: A115116 A141662 A328383 * A248886 A123884 A178412
KEYWORD
base,more,nonn
AUTHOR
Amarnath Murthy, Sep 21 2003
EXTENSIONS
a(8) from David Wasserman, Jul 01 2005
a(9) from Dmitry Petukhov, Oct 15 2017
STATUS
approved