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A379963
Numbers k such that A276086(k)+1 is a perfect square (A000290), where A276086 is the primorial base exp-function.
0
2, 8, 34, 36, 214, 248, 254, 2318, 2350, 2520, 2564, 2776, 5076, 30038, 30092, 30480, 32374, 510542, 510728, 510746, 512886, 515134, 540540, 540818, 542862, 542888, 1021442, 9699702, 9699722, 9699772, 9699788, 9702010, 9702256, 9729938, 9734358, 10210414, 10217558, 10240472, 10240724, 19401924, 19429870, 19912238
OFFSET
1,1
EXAMPLE
A276086(34) = 63, +1 = 64 = 8^2, therefore 34 is included.
A276086(36) = 35, +1 = 36 = 6^2, therefore 36 is included.
PROG
(PARI)
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
is_A379963(n) = issquare(1+A276086(n));
CROSSREFS
Subsequence of A379962.
Cf. also A379965 and A328849 (numbers k such that A276086(k) is a square).
Sequence in context: A191551 A263627 A172448 * A268601 A026577 A204090
KEYWORD
nonn,new
AUTHOR
Antti Karttunen, Jan 24 2025
STATUS
approved