A347114 - OEIS

%I #14 Mar 26 2022 19:12:57

%S 1386470925,1423809765,1463095872,1536942870,1560837942,1583406972,

%T 1640538297,1738402695,1765403829,1795023846,1920538647,2056743198,

%U 2076149583,2089571436,2097384615,2301546897,2386051749,2453718609,2531869704,2587063149,2605431798

%N Heptagonal pandigitals.

%C There are 53 pandigital heptagonal numbers with no repeated digits, i.e., 10-digit pandigital heptagonal numbers. - _Harvey P. Dale_, Mar 26 2022

%F Intersection of A000566 (heptagonal numbers) and A171102 (infinite pandigital numbers).

%t h[n_] := n*(5*n - 3)/2; Select[h /@ Range[33000], Length @ DeleteDuplicates @ IntegerDigits[#] == 10 &] (* _Amiram Eldar_, Aug 19 2021 *)

%t Select[PolygonalNumber[7,Range[20234,62854]],Sort[IntegerDigits[#]] == Range[ 0,9]&] (* _Harvey P. Dale_, Mar 26 2022 *)

%o (Sage)

%o A000566 = list(int(n*(5*n-3)/2) for n in range(0,1000000))

%o def haspan(s): return any(len(set(s[i:i+10]))==10 for i in range(len(s)-9))

%o A347114 = list(elem for elem in A000566 if haspan(str(elem)))

%Y Cf. A000566, A171102.

%K nonn,base,less

%O 1,1

%A _Dumitru Damian_, Aug 19 2021