A086043
Concatenation of first n twin primes.
Original entry on oeis.org
3, 35, 357, 35711, 3571113, 357111317, 35711131719, 3571113171929, 357111317192931, 35711131719293141, 3571113171929314143, 357111317192931414359, 35711131719293141435961, 3571113171929314143596171, 357111317192931414359617173, 357111317192931414359617173101
Offset: 1
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Primes:= select(isprime, {seq(i,i=1..100,2)}):
T1:= Primes intersect map(`+`,Primes,2):
Twins:= sort(convert(T1 union map(`-`,T1,2),list)):
dcat:= (a,b) -> a*10^(1+ilog10(b))+b:
A[1]:= 3:
for n from 2 to nops(Twins) do A[n]:= dcat(A[n-1],Twins[n]) od:
seq(A[i],i=1..nops(Twins)); # Robert Israel, Sep 01 2016
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Table[FromDigits@ Flatten@ Map[IntegerDigits, Take[#, n]], {n, Length@ #}] &[Union@ Join[#, # + 2] &@ Select[Prime@ Range@ 17, NextPrime@ # - 2 == # &]] (* Michael De Vlieger, Sep 01 2016 *)
Module[{tps=Union[Flatten[Select[Partition[Prime[Range[50]],2,1],#[[2]]-#[[1]] == 2&]]]},FromDigits[Flatten[IntegerDigits/@#]]&/@Table[Take[tps,n],{n,Length[tps]}]] (* Harvey P. Dale, Jun 16 2022 *)
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concattwprb(n) = { y=3; forprime(x=5,n, if(isprime(x+2) || isprime(x-2), y=eval(concat(Str(y),Str(x))); print1(y",") ) ) }
A132938
Concatenation of first n Bell numbers.
Original entry on oeis.org
1, 11, 112, 1125, 112515, 11251552, 11251552203, 11251552203877, 112515522038774140, 11251552203877414021147, 11251552203877414021147115975, 11251552203877414021147115975678570
Offset: 0
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Module[{nn=20,b},b=BellB[Range[0,nn]];Table[FromDigits[Flatten[ IntegerDigits/@ Take[b,n]]],{n,nn}]] (* Harvey P. Dale, Mar 01 2020 *)
A132937
Concatenation of first n odd isolated primes.
Original entry on oeis.org
23, 2337, 233747, 23374753, 2337475367, 233747536779, 23374753677983, 2337475367798389, 233747536779838997, 233747536779838997113, 233747536779838997113127, 233747536779838997113127131
Offset: 1
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With[{ips=Transpose[Select[Partition[Prime[Range[2,50]],3,1], Min[ Differences[#]]>2&]][[2]]},Table[FromDigits[Flatten[ IntegerDigits/@ Take[ips,n]]],{n,Length[ips]}]] (* Harvey P. Dale, Sep 17 2013 *)
A132931
Concatenation of first n Mersenne primes.
Original entry on oeis.org
3, 37, 3731, 3731127, 37311278191, 37311278191131071, 37311278191131071524287, 373112781911310715242872147483647, 3731127819113107152428721474836472305843009213693951
Offset: 1
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Module[{nn=15,mp},mp=2^MersennePrimeExponent[Range[nn]]-1;Table[FromDigits[Flatten[ IntegerDigits/@Take[mp,n]]],{n,nn}]] (* Harvey P. Dale, Aug 25 2023 *)
A132936
Concatenation of first n isolated primes.
Original entry on oeis.org
2, 223, 22337, 2233747, 223374753, 22337475367, 2233747536779, 223374753677983, 22337475367798389, 2233747536779838997, 2233747536779838997113, 2233747536779838997113127
Offset: 1
A132939
Concatenate Motzkin numbers (A001006).
Original entry on oeis.org
1, 11, 112, 1124, 11249, 1124921, 112492151, 112492151127, 112492151127323, 112492151127323835, 1124921511273238352188, 11249215112732383521885798, 1124921511273238352188579815511, 112492151127323835218857981551141835
Offset: 0
Showing 1-6 of 6 results.
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