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A156615 a(1)=2, a(n+1) is the smallest prime > n*final digit of a(n). 6

%I #9 Jun 18 2022 15:57:34

%S 2,3,7,23,13,17,43,23,29,83,31,13,37,97,101,17,113,53,59,173,61,23,67,

%T 163,73,79,239,251,29,263,97,223,97,233,103,107,257,263,127,277,281,

%U 43,127,307,311,47,331,53,149,443,151,53,157,373,163,167

%N a(1)=2, a(n+1) is the smallest prime > n*final digit of a(n).

%e 2, 3 (>2=1*2), 7 (>6=2*3), 23 (>21=3*7).

%p A010879 := proc(n) n mod 10 ;end:A156615 := proc(n) option remember ; if n = 1 then 2; else nextprime((n-1)*A010879(procname(n-1))) ; fi; end: L := [seq(A156615(n),n=1..80)] ;

%o (PARI) print1(t=2);for(n=2,99,print1(", ", t=nextprime(t%10*n))) \\ _Charles R Greathouse IV_, Dec 29 2012

%K nonn,base,less

%O 1,1

%A _Juri-Stepan Gerasimov_, Feb 11 2009

%E Corrected from a(2) on, corrected erroneous examples. Added keywords base,less _R. J. Mathar_, Feb 13 2009

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Last modified May 1 21:53 EDT 2024. Contains 372177 sequences. (Running on oeis4.)