A379963 Numbers k such that A276086(k)+1 is a perfect square (A000290), where A276086 is the primorial base exp-function.

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

Author

Antti Karttunen, Jan 24 2025

Keywords

• nonn

Examples

			A276086(34) = 63, +1 = 64 = 8^2, therefore 34 is included.
A276086(36) = 35, +1 = 36 = 6^2, therefore 36 is included.
		

Links

• Antti Karttunen, Table of n, a(n) for n = 1..82
• Index entries for sequences related to primorial base.

Crossrefs

Subsequence of A379962.

Cf. A000290, A002110, A276086.

Cf. also A379965 and A328849 (numbers k such that A276086(k) is a square).

Programs

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));