A133015
Concatenation of next n positive triangular numbers.
Original entry on oeis.org
1, 36, 101521, 28364555, 667891105120, 136153171190210231, 253276300325351378406, 435465496528561595630666, 7037417808208619039469901035, 1081112811761225127513261378143114851540
Offset: 1
A133060
Concatenation of next n twin primes.
Original entry on oeis.org
3, 57, 111317, 19293141, 4359617173, 101103107109137139, 149151179181191193197, 199227229239241269271281, 283311313347349419421431433, 461463521523569571599601617619
Offset: 1
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Module[{pp=200,tps},tps=Union[Flatten[Select[Partition[Prime[Range[ pp]],2,1],#[[2]]-#[[1]]==2&]]];FromDigits[Flatten[ IntegerDigits/@#]]&/@ TakeList[tps,Range[Floor[(Sqrt[1+8Length[tps]]-1)/2]]]] (* Harvey P. Dale, Apr 06 2022 *)
A134725
Concatenation of next n squares of positive integers.
Original entry on oeis.org
1, 49, 162536, 496481100, 121144169196225, 256289324361400441, 484529576625676729784, 84190096110241089115612251296, 136914441521160016811764184919362025
Offset: 1
A134726
Concatenation of next n cubes of positive integers.
Original entry on oeis.org
1, 827, 64125216, 3435127291000, 13311728219727443375, 409649135832685980009261, 10648121671382415625175761968321952, 2438927000297913276835937393044287546656
Offset: 1
A134728
Concatenation of next n perfect numbers.
Original entry on oeis.org
6, 28496, 8128335503368589869056, 13743869132823058430081399521282658455991569831744654692615953842176191561942608236107294793378084303638130997321548169216
Offset: 1
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Module[{nn=5},FromDigits[Flatten[IntegerDigits/@#]]&/@TakeList[ PerfectNumber[ Range[ (nn(nn+1))/2]],Range[nn]]] (* Harvey P. Dale, Apr 04 2022 *)
A134729
Concatenation of next n Sophie Germain primes A005384(n).
Original entry on oeis.org
2, 35, 112329, 41538389, 113131173179191, 233239251281293359, 419431443491509593641, 653659683719743761809911, 95310131019103110491103122312291289, 1409143914511481149915111559158316011733, 18111889190119311973200320392063206921292141
Offset: 1
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With[{sgp=Select[Prime[Range[500]],PrimeQ[2#+1]&]},Table[ FromDigits[ Flatten[IntegerDigits/@Take[sgp,{(n(n+1))/2+1,((n+1)(n+2))/2}]]],{n,0,11}]] (* Harvey P. Dale, Mar 24 2013 *)
A134793
Concatenation of next n nonprime numbers.
Original entry on oeis.org
1, 46, 8910, 12141516, 1820212224, 252627283032, 33343536383940, 4244454648495051, 525455565758606263, 64656668697072747576, 7778808182848586878890, 9192939495969899100102104105, 106108110111112114115116117118119120121
Offset: 1
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Module[{upto=35,comps,nn},nn=(upto(upto+1))/2;comps=Select[Range[nn], !PrimeQ[#]&];Table[FromDigits[Flatten[IntegerDigits/@Take[comps, {((i-1)(i))/2+1, (i(i+1))/2}]]],{i,25}]] (* Harvey P. Dale, Sep 10 2013 *)
A134796
Concatenation of next n positive oblong numbers.
Original entry on oeis.org
2, 612, 203042, 567290110, 132156182210240, 272306342380420462, 506552600650702756812, 87093099210561122119012601332, 140614821560164017221806189219802070
Offset: 1
A134821
Concatenation of next n Motzkin numbers.
Original entry on oeis.org
1, 12, 4921, 51127323835, 218857981551141835113634, 310572853467235677965363821819928450852019, 1425475594007632231129760415319272779790434025012566981847673007772802
Offset: 1
A193381
Largest multiple of n which is a concatenation of the n numbers n(n-1)/2,...,n(n+1)/2-1, or 0 if no such number exists.
Original entry on oeis.org
0, 12, 543, 9876, 1413121110, 201918171516, 27262524212322, 3534333231302928, 444342414039383736, 54535251494847464550, 6564636261605958575655, 777675747372717069676668, 90898887868584838281798078, 999897969594939291104103101102100
Offset: 1
a(20) = concat(210,209,...,201,199,...,191,200).
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lmn[n_]:=Max[Select[FromDigits[Flatten[IntegerDigits/@#]]&/@Permutations[n],Divisible[ #,Length[n]]&]]; Join[{0},lmn/@With[{nn=10},TakeList[Range[(nn(nn+1))/2],Range[2,nn]]]] (* The program generates the first 10 terms of the sequence. To generate more, increase the nn constant but the program may take a long time to run. *) (* Harvey P. Dale, Nov 20 2023 *)
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a(n)={my(d=vecsort(vector(n,i,Str(n*(n-1)/2-1+i)),,4),t); for(i=1,n!, eval(concat(d))%n || return(eval(concat(d))); d=precperm(d))} /* see A076072 for precperm() */
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