This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A209204 #19 Nov 22 2021 10:06:57 %S A209204 84,114,138,168,258,324,348,462,552,588,684,714,744,798,882,894,972, %T A209204 1176,1602,1734,2196,2256,2442,2478,2568,2646,2658,2688,3036,3162, %U A209204 3444,3906,4524,5154,5406,5544,5766,5796,6018,6456,6594,6636,6936,7272,7938,8736 %N A209204 Values of the difference d for 5 primes in geometric-arithmetic progression with the minimal sequence {5*5^j + j*d}, j = 0 to 4. %C A209204 A geometric-arithmetic progression of primes is a set of k primes (denoted by GAP-k) of the form p r^j + j d for fixed p, r and d and consecutive j. Symbolically, for r = 1, this sequence simplifies to the familiar primes in arithmetic progression (denoted by AP-k). The computations were done without any assumptions on the form of d. Primality requires d to be multiple of 3# = 6 and coprime to 5. %C A209204 Subsequence of A209203. - _Zak Seidov_, Jul 06 2013 %H A209204 Sameen Ahmed Khan, <a href="/A209204/b209204.txt">Table of n, a(n) for n = 1..10000</a> %H A209204 Sameen Ahmed Khan, <a href="http://arxiv.org/abs/1203.2083/">Primes in Geometric-Arithmetic Progression</a>, arXiv:1203.2083v1 [math.NT], (Mar 09 2012). %e A209204 d = 114 then {5*5^j + j*d}, j = 0 to 4, is {5, 139, 353, 967, 3581}, which is 5 primes in geometric-arithmetic progression. %t A209204 p = 5; gapset5d = {}; Do[If[PrimeQ[{p, p*p + d, p*p^2 + 2*d, p*p^3 + 3*d, p*p^4 + 4*d}] == {True, True, True, True, True}, AppendTo[gapset5d, d]], {d, 2, 10000, 2}]; gapset5d %Y A209204 Cf. A172367, A209202, A209203, A209205, A209206, A209207, A209208, A209209, A209210. %K A209204 nonn %O A209204 1,1 %A A209204 _Sameen Ahmed Khan_, Mar 06 2012