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 A173550 a(n) = k smallest exponent of N = 2^k of first prime(1) = 2 where string "p(1) ... p(n)" appears in the decimal representation of N (n=1,2,...). 0
 1, 41, 81, 256, 2810, 19680, 131516, 1812049 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 REFERENCES Julian Havil, Impossible?: Surprising Solutions to Counterintuitive Conundrums, Princeton University Press 2008 LINKS EXAMPLE n=1: 2^1 = 2 n=2: 2^41 = 2199023255552, "23" appears on decimals 6-7 n=3: 2^81 = 2417851639229258349412352, "235" appears on decimals 22-24 n=4: 2^256 has 78 decimals, "2357" appears on decimals 20-23 2^256 = 115792089237316195423570985008687907853269984665640564039457584007913129639936 CROSSREFS Cf. A000079, A018802, A171132, A171242, A171489, A171652, A171768 Sequence in context: A044107 A044488 A335482 * A136072 A098061 A141898 Adjacent sequences: A173547 A173548 A173549 * A173551 A173552 A173553 KEYWORD nonn,base AUTHOR Eva-Maria Zschorn (e-m.zschorn(AT)zaschendorf.km3.de), Feb 21 2010 EXTENSIONS Extended and edited by Hans Havermann, Mar 20 2010 STATUS approved

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Last modified December 7 12:27 EST 2022. Contains 358656 sequences. (Running on oeis4.)