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A049857 Concatenate prevprime(n), n, and nextprime(n). 0
235, 345, 357, 567, 5711, 7811, 7911, 71011, 71113, 111213, 111317, 131417, 131517, 131617, 131719, 171819, 171923, 192023, 192123, 192223, 192329, 232429, 232529, 232629, 232729, 232829, 232931, 293031, 293137, 313237 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

LINKS

Table of n, a(n) for n=3..32.

MAPLE

P:=proc(i) local a, n; for n from 3 by 1 to i do a:=prevprime(n)*10^floor(evalf(log10(nextprime(n))+1, 100)+floor(evalf(log10(n)+1, 100)))+n*10^floor(evalf(log10(nextprime(n))+1, 100))+nextprime(n); print(a); od; end: P(100); # Paolo P. Lava, Jan 21 2009

MATHEMATICA

FromDigits[Flatten[IntegerDigits/@#]]&/@Table[{NextPrime[n, -1], n, NextPrime[n]}, {n, 3, 40}] (* Harvey P. Dale, Dec 02 2019 *)

PROG

(PARI) a(n) = eval(concat(Str(precprime(n-1)), concat(Str(n), Str(nextprime(n+1))))); \\ Michel Marcus, Aug 11 2017

CROSSREFS

Cf. A151799, A151800.

Sequence in context: A185482 A036209 A077803 * A218038 A132903 A247474

Adjacent sequences:  A049854 A049855 A049856 * A049858 A049859 A049860

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified May 16 10:30 EDT 2021. Contains 343941 sequences. (Running on oeis4.)