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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

Table of n, a(n) for n=1..8.

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.)