A346494 Heptagonal numbers (A000566) with prime indices (A000040).
7, 18, 55, 112, 286, 403, 697, 874, 1288, 2059, 2356, 3367, 4141, 4558, 5452, 6943, 8614, 9211, 11122, 12496, 13213, 15484, 17098, 19669, 23377, 25351, 26368, 28462, 29539, 31753, 40132, 42706, 46717, 48094, 55279, 56776, 61387, 66178, 69472, 74563, 79834
Offset: 1
Examples
a(1) = Heptagonal(prime(1)) = A000566(2) = 2*(5*2-3)/2 = 7; a(2) = Heptagonal(prime(2)) = A000566(3) = 3*(5*3-3)/2 = 18; a(3) = Heptagonal(prime(3)) = A000566(5) = 5*(5*5-3)/2 = 55.
Programs
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Mathematica
A346494[n_] := PolygonalNumber[7, Prime[n]]; Table[A346494[n], {n, 1, 41}] (* Robert P. P. McKone, Aug 22 2021 *)
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PARI
a(n) = my(p=prime(n)); p*(5*p-3)/2; \\ Michel Marcus, Sep 16 2021
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Python
from sympy import primerange print([p*(5*p-3)//2 for p in primerange(1, 180)]) # Michael S. Branicky, Aug 22 2021
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Sage
A = [int(p*(5*p-3)/2) for p in range(0,10^3) if p in Primes()]