A104301
Primes which are the reverse concatenation of two consecutive square numbers.
Original entry on oeis.org
41, 6449, 196169, 576529, 11561089, 14441369, 27042601, 38443721, 51845041, 60845929, 67246561, 84648281, 1081610609, 2073620449, 2190421609, 2822427889, 3240032041, 4000039601, 4326442849, 5017649729, 5290052441, 6250062001, 7507674529, 8294482369, 103684103041
Offset: 1
The first term is 41 which is a prime and is the reverse concatenation of 1 and 4 which are two consecutive square numbers.
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cat[s_] := FromDigits[Flatten[IntegerDigits[s]]]; Select[cat /@ Reverse /@ Partition[Range[350]^2, 2, 1], PrimeQ] (* Amiram Eldar, Jul 15 2025 *)
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from sympy import isprime
A104301_list = []
for n in range(1, 2000):
x = int(str((n+1)**2)+str(n**2))
if isprime(x):
A104301_list.append(x) # Chai Wah Wu, Sep 13 2014
A104302
Primes which are the reverse concatenation of three consecutive square numbers.
Original entry on oeis.org
941, 25169, 169144121, 302529162809, 110251081610609, 166411638416129, 497294928448841, 580815760057121, 930259241691809, 123201122500121801, 139129138384137641, 140625139876139129, 196249195364194481, 214369213444212521, 235225234256233289, 261121260100259081
Offset: 1
The first term is 941 which is a prime and is the reverse concatenation of 1, 4 and 9 which are three consecutive square numbers.
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Select[FromDigits[Flatten[IntegerDigits/@#]]&/@(Reverse/@Partition[Range[500]^2,3,1]),PrimeQ] (* Harvey P. Dale, Sep 21 2024 *)
A104304
Primes which are the reverse concatenation of five consecutive square numbers.
Original entry on oeis.org
1876918496182251795617689, 3648136100357213534434969, 297025295936294849293764292681, 466489465124463761462400461041, 16770251674436167184916692641666681, 17556251752976175032917476841745041, 30660013062500305900130555043052009, 31506253147076314352931399843136441
Offset: 1
The first term is 1876918496182251795617689 which is a prime and is the reverse concatenation of 17689, 17956, 18225, 18496 and 18769 which are five consecutive square numbers.
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cat[s_] := FromDigits[Flatten[IntegerDigits[s]]]; Select[cat /@ Reverse /@ Partition[Range[3000]^2, 5, 1], PrimeQ] (* Amiram Eldar, Jul 15 2025 *)
Showing 1-3 of 3 results.