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 A052092 Lengths of the palindromic primes from Honaker's sequence A053600. 5
 1, 3, 5, 9, 11, 15, 19, 23, 25, 31, 35, 41, 45, 49, 55, 59, 63, 69, 75, 81, 87, 93, 99, 105, 109, 113, 119, 125, 129, 133, 139, 145, 151, 157, 161, 167, 173, 179, 185, 191, 195, 201, 207, 213, 219, 225, 231, 237, 243, 249, 255, 261, 267, 273, 279, 285, 291, 297 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Since the terms from a(34) onward are currently only probable primes, the lengths given in this sequence beyond that point are only provisional. For n > 0, a(n) = a(n-1)+2*m where m is the number of digits of A052091(n). - Chai Wah Wu, Dec 03 2015 LINKS Chai Wah Wu, Table of n, a(n) for n = 0..501 PROG (Python) from sympy import isprime A052092_list, l, p = [1], 1, 2 for _ in range(100):     m, ps = 1, str(p)     s = int('1'+ps+'1')     while not isprime(s):         m += 1         ms = str(m)         if ms[0] in '268':             ms = str(int(ms[0])+1) + '0'*(len(ms)-1)             m = int(ms)         if ms[0] in '45':             ms = '7' + '0'*(len(ms)-1)             m = int(ms)         s = int(ms+ps+ms[::-1])     p = s     l += 2*len(ms)     A052092_list.append(l) # Chai Wah Wu, Dec 02 2015 CROSSREFS Cf. A052091, A053600, A047076. Sequence in context: A287421 A214214 A281505 * A075991 A292918 A216091 Adjacent sequences:  A052089 A052090 A052091 * A052093 A052094 A052095 KEYWORD nonn,base AUTHOR Patrick De Geest, Jan 15 2000 EXTENSIONS Comments from G. L. Honaker, Jr., Mar 30 2000 Edited by T. D. Noe, Oct 30 2008 STATUS approved

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Last modified December 2 16:46 EST 2020. Contains 338877 sequences. (Running on oeis4.)