%I #17 Jul 08 2024 13:18:12

%S 1,6,15,28,45,66,91,12,45,82,123,168,217,27,84,145,21,9,82,159,24,19,

%T 18,111,28,129,234,343,456,573,694,819,948,181,318,459,64,213,366,523,

%U 684,849,118,291,468,649,834,123,316,513,714,919,1128,1341,1558,1779

%N a(1) = 1; for n >= 2, a(n) = noz(a(n-1) + 4*n - 3), where noz(n) = A004719(n).

%C Zeroless analog of the positive hexagonal numbers.

%H Paolo Xausa, <a href="/A373172/b373172.txt">Table of n, a(n) for n = 1..10000</a>

%t noz[n_] := FromDigits[DeleteCases[IntegerDigits[n], 0]];

%t Block[{n = 1}, NestList[noz[++n*4 - 3 + #] &, 1, 100]]

%t nxt[{n_,a_}]:={n+1,FromDigits[DeleteCases[IntegerDigits[a+4n+1],0]]}; NestList[nxt,{1,1},60][[;;,2]] (* _Harvey P. Dale_, Jul 08 2024 *)

%o (PARI) noz(n) = fromdigits(select(sign, digits(n))); \\ A004719

%o lista(nn) = my(va=vector(nn)); for (n=1, nn, va[n] = if (n==1, 1, noz(va[n-1] + 4*n - 3))); va; \\ _Michel Marcus_, Jun 03 2024

%Y Row n = 6 of A373169.

%Y Cf. A000384, A004719, A243658, A370812, A373171.

%K nonn,base,easy

%O 1,2

%A _Paolo Xausa_, May 28 2024