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 A256884 #23 Mar 13 2025 16:43:43 %S A256884 0,10,21,40,63,84,90,105,130,140,150,160,165,170,175,210,252,276,324, %T A256884 330,336,345,360,390,405,420,520,560,600,630,640,650,660,680,700,735, %U A256884 770,840,861,910,1008,1044,1050,1092,1104,1110,1170,1260,1284,1290,1296,1320,1344,1350,1365,1380,1407,1410,1440,1470,1533,1560,1620 %N A256884 Numbers divisible by prime(d+1) for each digit d of their base-4 representation. %C A256884 The base-4 variant of A256882, A256883, A256865, ..., A256870 in bases 2, ..., 10. %C A256884 A variant of A256874 where digits 0 are forbidden and divisibility by prime(d) is required. %H A256884 Harvey P. Dale, <a href="/A256884/b256884.txt">Table of n, a(n) for n = 1..1000</a> %e A256884 0 is divisible by prime(0+1)=2. %e A256884 10 = 22_4 and is divisible by prime(2+1)=5. %e A256884 n = 1, 2, 3 are not divisible by prime(n+1) = 3, 5, 7; nor are 4=10_4, 5=11_4, and 7=13_4 divisible by prime(1+1) = 3; nor are 6=12_4, 8=20_4, 9=21_4 divisible by prime(2+1)=5. %t A256884 Select[Range[0,2000],AllTrue[#/(Prime[#+1]&/@IntegerDigits[#,4]),IntegerQ]&] (* _Harvey P. Dale_, Mar 13 2025 *) %o A256884 (PARI) is(n,b=4)=!for(i=1,#d=Set(digits(n,b)),n%prime(d[i]+1)&&return) %Y A256884 Cf. A256882, A256883, A256865-A256870, A256874-A256879, A256786. %K A256884 nonn,base %O A256884 1,2 %A A256884 _M. F. Hasler_, Apr 11 2015