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 A256048 Smallest palindromic prime by adding at least one digit to both the left and right of n 2
 101, 313, 727, 131, 11411, 151, 10601, 373, 181, 191, 30103, 1114111, 1120211, 11311, 11411, 31513, 1160611, 1117111, 18181, 71917, 30203, 1120211, 72227, 32323, 12421, 1250521, 36263, 12721, 12821, 39293, 10301, 11311, 32323, 13331, 14341, 33533, 16361, 77377 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS Chai Wah Wu, Table of n, a(n) for n = 0..10000 PROG (Python) from __future__ import division from sympy import isprime def palgenrange2(m, l): # generator of odd-length palindromes of length at least m and at most 2*l ....if m == 1: ........yield 0 ....for x in range(m//2+1, l+1): ........n = 10**(x-1) ........for y in range(n, n*10): ............s = str(y) ............yield int(s+s[-2::-1]) def A256048(n): ....sn = str(n) ....for p in palgenrange2(len(sn)+2, len(sn)+20): ........if sn in str(p)[1:-1] and isprime(p): ............break ....else: ........return 'search limit reached' ....return p # Chai Wah Wu, Mar 22 2015 CROSSREFS Cf. A090287 Sequence in context: A139701 A195294 A142578 * A252942 A090287 A134971 Adjacent sequences:  A256045 A256046 A256047 * A256049 A256050 A256051 KEYWORD nonn,base AUTHOR Felix FrÃ¶hlich, Mar 10 2015 EXTENSIONS a(10), a(12), a(16), a(18) corrected by Chai Wah Wu, Mar 22 2015 STATUS approved

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Last modified November 26 17:52 EST 2021. Contains 349343 sequences. (Running on oeis4.)